← The Dr. Gabrielle Lyon Show
The Dr. Gabrielle Lyon Show
The Truth About Nutrition: How You Can Take a Science-Based Approach | Bradley Johnston PhD
01:30:53
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- [00:00]
Dr. Gabrielle Lyon
The loaded term and phenomenon of misinformation has left many Americans asking, what if everything I know about nutrition is wrong? How often have we trusted headlines only to find years later the advice was misleading or incomplete? From demonizing red meat to hyping plant based diets, nutrition science has become a battleground for conflicting advice and misconceptions. Hi, I'm Dr. Gabrielle Lyon and today we're cutting through the noise to uncover the truth about what we really know about nutrition. Joining me is Dr. Bradley Johnston, a world renowned expert and researcher who's reshaping the way we think about food and health. With almost 200 peer reviewed papers, Dr. Johnston has been at the forefront of nutrition science, who has tackled some of the most intense topics. His groundbreaking studies have sparked global debates and even challenged the advice from organizations like the World Health Organization. In this episode, we'll tackle how much influence we have over the dietary advice we're told to trust. We're also going behind the scenes to explore how public health policies are shaped, uncover hidden biases in nutrition science, and give you actionable tips for making smarter food choices backed by evidence, not hype. So, my friends, if you've ever felt overwhelmed by conflicting advice about what to eat or you've questioned whether you're getting the full story, this episode is for you.
- [01:45]
Dr. Bradley Johnston
Check.
- [01:45]
Dr. Gabrielle Lyon
Join me as we separate fact from fiction when it comes to nutrition.
- [01:56]
Dr. Bradley Johnston
Dr. Bradley Johnston, welcome to the show. I am so thrilled to have you here. I've been a huge fan of your work. I think that you've done a tremendous job at helping us think about evidence based practices, how we can sift through information. And you have your PhD. You also, I believe that you're also a professor now.
- [02:19]
Dr. Gabrielle Lyon
Are you still, Are you teaching?
- [02:20]
Dr. Bradley Johnston
Yes, I'm a professor. Texas A and M University.
- [02:24]
Amazing. Amazing.
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Dr. Gabrielle Lyon
Tell us a little bit about your.
- [02:26]
Dr. Bradley Johnston
Background, what your PhD is in, how you became interested in the work that you're doing now.
- [02:32]
Yeah, sure. So thanks for asking. Thanks for having me. My undergraduate degree is in kinesiology and then I did doctoral training in experimental medicine at the University of Alberta and then from there did postdoctoral training in evidence based healthcare at Oxford University or University of Oxford and McMaster University in clinical epidemiology and biostatistics. And it was really at McMaster where my understanding and passion for evidence based practice and health research methodology, I should say human health research methodology really kind of was inspired.
- [03:15]
I would say it is all coming into focus for me now because one of our mutual colleagues, Stu Phillips, says McMaster's is the home of evidence based practices. Have you heard him say that?
- [03:28]
I haven't, but this is true. And my mentor when I was at McMaster, Dr. Gordon Guyett, is kind of the guy who coined the term evidence based medicine. And he's a wonderful mentor to this day and a great friend. So I've been very fortunate to work with him.
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The term is thrown around a lot. What is involved in studying evidence based.
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Dr. Gabrielle Lyon
And do you say evidence based medicine.
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Dr. Bradley Johnston
Or do you say evidence based practice? What would be the correct term?
- [03:57]
Yeah, good question. I think evidence based practice is a better term because it's applicable to medicine, nutrition, pharmacology, et cetera, et cetera, surgery. And it's really three central tenets of evidence based practice. Number one is, well, first you actually have to start with what is your clinical question or your public health question? So your target population, intervention, comparator, outcome. You're a clinician, so you're faced with clinical questions on a regular basis. Once you have clarity on that and what you're trying to resolve clinically or from a public health perspective, the first central tenet is using the best available evidence to answer that question. And it's usually not always in the form of systematic reviews, high quality up to date systematic reviews with meta analysis, or high quality up to date practice guidelines, whether it's a clinical practice guideline or a public health practice guideline. Second tenant is expertise. Dr. Lyon, you've got lots of clinical expertise that really matters. It's a part of evidence based practice. And the third tenant is it's not the evidence that drives the decision clinically. It should be the values and preferences of your client or your patient or your target population, if they're informed. If your patient or client or the population has an understanding and is informed about the best available evidence, that's quite fascinating.
- [05:35]
I don't think I've ever really thought about the tenants and how they would then apply. Right. As a clinician, you think, here's a problem, here's the outcome. For example, we want to help you lose body fat or lower your blood pressure. We then go to, you know, for physicians in the US or elsewhere, there's up to date.
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Dr. Gabrielle Lyon
It would be a database that pulls.
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Dr. Bradley Johnston
Together and utilizes all the information out there and then provides processes, algorithms to then treat.
- [06:11]
Yep.
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I have two questions. I suppose the first one is how did you become interested in that? Because you were interested in it before. I think it was a thing, you know, I don't exactly know how to put that in Terms before it was something to be thought of.
- [06:33]
Well, so my mentor, Dr. Guy, he's like I say the. One of the prime movers in that space. And his mentor was a guy by the name of Dave Sackett, who founded the McMaster Department of Clinical Epidemiology and Biostatistics. So it's evidence based medicine and practice has been around. I think the term was coined in around 1990 and.
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Which is.
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So it's.
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I mean, it's not that old.
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Yeah, for me it's kind of old, but like. Yeah, relatively speaking, it's. Yeah, it's only.
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Dr. Gabrielle Lyon
How true that.
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Dr. Bradley Johnston
Also that's after the dietary guidelines they didn't even put. They implemented dietary guidelines in 1980 was the first. Yeah. Evidence based practices then I suppose became something in 1990. That's wild.
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Yeah. So. So my interest, when I did my PhD at the University of Alberta, my summer job was working at the Evidence Based Practice center, which is, was sponsored by ahrq, which is a US organization. They have evidence based practice centers around the US and they used to have them and sponsor them in Canada. I don't think they're any longer in Canada. So I became somewhat inspired there. I got involved with the Cochrane Collaboration, started doing cochrane systematic reviews of the literature, particularly, particularly on probiotics for gastrointestinal infections. And then luckily I arrived at McMaster eventually and kind of learned firsthand from some of the prime movers.
- [08:10]
Was it the exploration of the information that was so fascinating or was it potentially trying to come to a conclusion? What was the driver in the process of thinking in that very unique way?
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Good question. I would say when you're in the space of people that are doing research that emphasize or have been trained in evidence based practice, at least at McMaster, there's a real emphasis on health research methods and understand and doing systematic reviews and getting an understanding of the methodology of randomized trials, cohort studies, case control studies, and eventually you as a trainee, you do more and more systematic reviews of the literature, meta analyses and you start to appreciate health research methods and how studies are done, the anatomy of studies and what's great and what's not so great. So. And then eventually I, I guess I found myself in a situation where I'd done a lot of different systematic reviews on quite disparate topics. And then I got into the space of doing some guideline work and realized that methods should be at the center of it. And people that have really strong understanding of the, of the, of the methodology of, of human research should Be kind of chairs or co chairs of guideline committees, at least from the McMaster perspective, which is kind of the, the foundational school that, that did a lot of the work, the foundational work in the space of evidence based practice, which would.
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Be a bit unusual in the way that when we think about guidelines, from my understanding they, for example, the aua, the American Urologic association, they will have urologists that study sexual medicine or andrology that will then inform the guidelines. I had never quite thought about the individual's ability to think about the foundation. Right. This is kind of the, I think maybe you called it the architecture of.
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Dr. Gabrielle Lyon
The study, which seems as if those.
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Dr. Bradley Johnston
Are two very separate qualifications. Is that fair to say?
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Yeah, really important is expertise in for example, a clinical area. But fundamentally important in guidelines is expertise in health research methods and being agnostic, ideally to what the data says. So that's really important too. We spend a lot of time when we're doing guidelines making sure that we're managing any potential conflicts of interest or disclosures upfront.
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That that must be challenging slightly. You know, I had Dr. Kevin Mackey on and Kevin Mackey, who is a epidemiologist by training. Do you, do you know Dr. Mackey?
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I definitely know the name. I've not met him.
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He's a wisdom neuro. I in fact believe you guys would get along quite well. Just wonderful human. And he said when he was in his training, he is a former president of the American Lipid Association.
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Okay, okay.
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And he said, I believed that cholesterol was going to be terrible. So he had come in with this preconceived notion that cholesterol was going to be very bad for an individual to eat. And when he did these rigorous evidence based practices, I'm assuming, and if you're listening, Dr. Mackey, I'm holding your feet to the fire. But he said it was absolutely not what he thought and he had to really begin to manage his bias and understanding that while he believed something, the evidence completely showed something else which caused him to actually learn a level of neutrality going into thinking about things.
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Yeah, well, I think maybe I don't know exactly what his, his research questions were that he was working on within this context. But another important component of evidence based practice is when we're working either from a systematic review level and definitely if you're doing a guideline is we spend time trying to understand and prioritize the outcomes that matter most to the target population. And it's usually not cholesterol unless the guideline is specific to, you know, best interventions to manage cholesterol or hypercholesterolemia. It's usually if you ask patients or members of the public, it's things like mortality, stroke, myocardial infarction, health related quality of life life. And so we spend a lot of time talking about this. The, the concept is often referred to as patient important outcomes. And it's, it's re. So you know, studies, whether it's clinical trials or observational studies, they measure lots of things. And for example, I'm the co chair of the Canadian Pediatric Obesity Management Guidelines that will be published sometime, hopefully early in 2025. We started that process by interviewing parents of children with obesity as well as experts in the field, but mostly parents of children to find out what outcomes matter most to them as a family and to their children or adolescents. And then once we understood that, we did systematic reviews of the literature and turns out that they said that the most important outcomes to them and based on their observations of their children were things like anxiety, depression, quality of life. And secondary to that was things like bmi, BMI Z weight. Right. So we kind of, we, we still did systematic reviews of bmi, BMI Z weight and different lipids but the, the outcomes that we really focused on were quality of life.
- [14:36]
Dr. Gabrielle Lyon
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- [16:02]
Dr. Bradley Johnston
That is fascinating and that really is the intertwining of the art and then of the medicine, at least that that's what that would represent to me that there's this art of practice in this human dynamic. And then actually, because I personally would have thought it would be something else, if I was thinking about the guidelines for physical activity in overweight or obese children, as a parent, I would think, okay, well I need them to be, I don't know, strong and an outcome of, I don't know, maybe I would think about their blood work or something like that, but maybe I wouldn't think about anxiety or something of that nature.
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Yeah. And of course we would get all that. We've collected all the data on lipids and blood pressure and anthropometrics. But also in addition, I think we're the first to do systematic reviews and use them to inform guidelines on essentially quality of life items or elements. Yeah.
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Why would someone, for those who don't know quite what evidence based practices are, why is it important to have them and to understand them?
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Yeah, really good question. Well, I would say that when I talked about the three central tenets, you know, if we kind of agree that we should focus on outcomes that matter most to our clients or to the public, and if we agree that we should use the best available evidence, human evidence, to drive our clinical or public health decisions, and if we agree that we should kind of this like you, you've talked about the, the art of medicine or, or let's say clinical practice, we should engagement with the values and preferences of, of the client. The philosophy of evidence based practice. And it is a philosophy. I'm not saying that there's this is the only way, but I think it's a very good way. It's been around for 40 years now and I think there's a lot of confusion. If we believe these things, if these things make sense, then ideally the client family should understand what does the evidence say and then they should be, should drive the decision. So we refer to it as value and preference sensitive decision making. It's often referred to as evidence based decision making. But maybe a more specific, maybe to be a bit more specific, it's value and preference sensitive decision making based on the best available evidence.
- [18:56]
What do you think confuses people the most, both clinicians, physicians or people? There's a lot of discussion around evidence based practices and we throw those terms around quite frequently. Myself, my colleagues will say this is evidence based practices, this is evidence informed. What do you think from both perspectives, both the lay public and the expert finds most, where would they be most misled or where would it be most confusing for them? Do you Think.
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Good question. It's a little tough to answer. We'd probably have to survey them to find out. But I would say my observation is there's a lot of confusion about what evidence based practice is and isn't. I would say that. Let's take an example. So we've done a systematic review and what we call a network meta analysis, which is a way to do comparative effectiveness research on all of the available randomized control trials that look at different dietary programs. And when I say programs, I mean diet plus lifestyle and as well as medication. So in, in people at cardiovascular risk, with considerable cardiovascular risk. So let's say they have obesity and their blood lipids are off, or they have obesity and they have high hypertension, what is the best available dietary program? So we, we did this systematic review, published it in British Medical Journal in 2023. We found 40 randomized control trials that look at hard outcomes like all cause mortality, myocardial infarction, stroke. We found 40 trials of seven different dietary programs. So things like the Mediterranean style diet, low fat diets, various versions of low fat, like low fat, very low fat. The best available evidence for the question what is the best dietary program to prevent major hard cardiovascular outcomes and mortality is Mediterranean style diet. So there's actually for the outcome, all cause mortality. There's seven randomized control trials, most of them are done in Europe, particularly in Spain. And the, the risk reduction, the absolute risk reduction over five years is 1.8%. So perhaps said in a more intuitive way, 18 fewer events per 1,000 people followed over five years. And this certainty of evidence, if we bring in the grade approach for that risk reduction is moderate. We concluded that there is moderate certainty evidence. The next best diet was a low fat diet. Now of course low fat is kind of code for higher fruits and vegetables, higher whole grains, clean meats, fish, that type of thing. For all cause mortality over five years, low fat diets were a 0.9% risk reduction. So not even 1%. 9. So nine fewer cases per 1,000. And both estimates were statistically significant. So if a, if you're working with a family or a patient, you can tell them the best, the best dietary programs are Mediterranean style and low fat. And here's what the, the absolute risk reductions are, here's the certainty of the evidence. And by the way, there was moderate certainty evidence for low fat as well. And they can make their own value and preference sensitive decisions. So that would be evidence based practice, perhaps done optimally. And I know as a physician you have limited time to do this kind of stuff.
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Time. Actually, my first visit with a patient will be an hour and a half to two hours.
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Ah.
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And our second visit will be hour and a half an hour.
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Okay, so you're an abnormal physician.
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Yes. And all the providers in our practice, we spend a tremendous amount of time getting to know our patient's favorite color and what their dog's name is. Everything. It's awesome. Can they find their socks? Whatever it is, when you are taking us through that process, it is, it.
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Dr. Gabrielle Lyon
Seems as if it's.
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Dr. Bradley Johnston
I don't want to say tedious, because there's a couple questions that I have. You know, as I think about this, the first thing that comes up is how do we ask the question? If we are looking at dietary programs and someone is thinking, does the question, are we asking the right question to get the answer that we're looking for? Does this make sense? So I'll. I'll give you an example.
- [24:03]
Sure.
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And this might not be the greatest example, but when I was doing my fellowship in geriatrics and nutritional sciences, the question was always, why are these individuals obese? Right. And there was this constant focus on obesity and body composition in that way, focus on fat. But when we switched the conversation and we began to examine why there were challenges with healthy skeletal muscle, we seemed to get. At least I did in my practice, I seemed to get better outcomes.
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Yeah, it makes sense right away, I think, well, people can probably control their skeletal muscle more than they can control their body fat.
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Exactly. And my question to you is, as we think about evidence based practices, because ultimately what we all want is we're all wanting to make people's lives better. You are doing that through examining evidence, making the evidence and the guidelines accessible in a way to provide a framework and an architecture for us to think about it. And then my job as a clinician is to go out and implement that. And when someone asks, for argument's sake, what is the best dietary program to reduce all cause mortality, the first step in my mind would be when you're thinking about evidence based practices, is we have to get the question right. Am I thinking about this in an appropriate manner?
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Yeah. Well, so ideally, our questions should be informed by our patients or members of the public. And so when I talked about the example of how we come up with the outcomes that are a part of our question, that in our case for the obesity management guidelines, was informed by parents and caregivers of those with children and adolescents with obesity, I'm not sure if I'm answering your question. Optimally. But yeah, the question is really, really important. Clear, clean, structured questions is. It's actually a skill in evidence. It's one of the competencies of evidence based practice.
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What are the. I don't want to get ahead of myself, but I'm curious as to what the process is to get to the right question. Because if we're not asking the right question and you know, we can interview our patients and they might not be able to verbalize appropriately what they want. But you know, as we begin to think about course correcting for the public and obviously evidence based practices could be exercise, it could be nutrition, it could be medication. Right. It could be all these various domains of health. Asking the right question seems like that, that is probably a challenge. You said that that's a skill. So what are the core competencies for understanding evidence based practices?
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Yeah. Or for being evidence based.
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Yeah.
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Right. Good question. So, open network paper from 2018. I forget the first author's name, but my mentor, Dr. Guy and other leads in evidence based medicine practice were a part of basically a Delphi study where they tried to figure out for the health professions what are the core competencies that they need to have. They, they came up with 68 core competencies. So that's a lot. And it's competencies.
- [27:44]
Can you get that online? And that. Is that a. Can I get that certificate online?
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Yeah, it, it'll only take you two years there. There's competencies in treatment, prevention, prognosis and diagnosis. But if we, if we narrow the scope and think about nutrition, I think nutrition, like registered dietitians, they usually are working with treatment and prevention. And one of my graduate students, Ruth Ghosh, has led recently a systematic review of the competencies of nutrition professionals and students. Like at least what the literature says. We don't actually know what their competencies are, but we have insights from the literature and we came up with her paper, we boiled it down to what we think are six core core competencies. And they are one asking a clear, clean question, a structured question to skills in finding the literature to answer that question. So you talked about up to date, but also skills in searching PubMed, which is a free version of Medline for your listeners. If you want to search the literature, there's other databases like Dynamed that kind of brings the best available evidence together for given clinical questions or public health questions. The third competency is skills in essentially assessing risk of bias and determining the methodological quality of a study, whether it be a randomized trial, a cohort study, or A systematic review of those studies. Fourth competency, and this one is really important, and it's often left out is competencies and understanding treatment or exposure effects. Right? So everybody knows about P values and statistical significance. But what we really need to know to make informed decisions is the average effect. Is it trivial, small, moderate or large, or perhaps very large? And so there we look at the point estimate like we start with looking at the relative effects, relative risk odds ratio, hazard ratio. But ideally the data needs to be presented also as an absolute estimate of effects. So a risk difference or an absolute risk reduction or increase, which are much more intuitive for decision makers. So that's the fourth competency. And number five is the certainty of evidence, Right? So you have a risk reduction. So let's go back to the example if I could, on dietary programs for reducing hard cardiovascular outcomes and mortality. Mediterranean style dietary program had the best available evidence, a 1.8% risk reduction. Again, the certainty of evidence was moderate, but it could have been possibly high or low or perhaps very low if it's informed by the grade approach. So an estimate of effect in a P value without some indication of how certain we are in that estimate of effect to me is kind of meaningless if you really want to have make informed decisions.
- [31:06]
Dr. Gabrielle Lyon
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- [32:55]
Dr. Bradley Johnston
Let's get started.
- [32:57]
And then the. Which competency am I on? The. The la. The next competency is essentially values and preferences. Right.
- [33:10]
So which is probably the easiest one? Right. It's what does the.
- [33:14]
Dr. Gabrielle Lyon
The individual one.
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Dr. Bradley Johnston
Yeah, but like you say, it's an art. So if your patient or the public understand what the absolute risk reduction is or increase what, how certain we are in those estimates of effect for outcomes that really matter to your patient or to the public, then the art of working with them around their values and preferences to find out what works for them is really important. And that depends on their kind of unique clinical situation, maybe their, their income, all kinds of things. Right. If you ask if the best evidence is a Mediterranean style diet and it's quite expensive to do that, or people live in a food desert, it's probably very unlikely that they're going to be able to follow a Mediterranean style diet to reduce their risk of all cause mortality over the next five years.
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When you had said based on the best available evidence, if someone is wanting to have an evidence based practice or for themselves, how much evidence is required to say? Okay, because I think that when you look at the Mediterranean diet you had mentioned, was there, was it 40 or was it seven?
- [34:30]
Dr. Gabrielle Lyon
There was somewhere.
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Dr. Bradley Johnston
How many studies were evaluated?
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Oh, seven. Seven trials on seven trials on the Mediterranean style diet for the outcome all cause mortality and in fact I think there's now eight.
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Amazing. In my mind I'm thinking, okay, well that's only seven, but perhaps, you know, two would be enough. How. When can we say there's enough data to have an evidence based practice?
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Interesting. Well, it actually more important than the number of studies is the size of the, of the studies, how many participants were enrolled and followed and completed. Completed. If it's an experimental study, it's different. We have lots of very large cohort studies. It doesn't necessarily mean that we have a lot of certainty in those estimates of effect. But you look at the number of studies, you look at the sample size and then ideally there's at least a few studies that have replicated the finding in different geographic regions.
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Is there? Do you think that there is and this is just a personal question in the way that, do you think that there's risk if we are not doing evidence based practices. Meaning, you know, I don't know, do you? Because you spent your life studying this, really bringing this process forward.
- [36:07]
Well, there's a risk in that we can have walk backs if we got it wrong in terms of the recommendations that we, that we've made. So, and that, that that's a risk. And you risk the trust of the public, for example, or the trust of your patient or your patient base if you, if it turns out that you're making recommendations either at a clinical level or a public health level where the evidence eventually shows you something quite different. Right. So a good example in nutrition that's often used is for years we thought that antioxidants would reduce cardiovascular events, but it was largely based on observational studies. Then they did a large randomized control trial of antioxidants, but this time in kind of supplemental form.
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This is vitamin E, one of those.
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It doesn't matter what, there's vitamin, vitamin C and also antioxidant combinations. And there's a Cochrane review that basically shows there's no difference in hard patient important outcomes and in fact there's a small possibility of risk. So we don't generally, I think most people know now that there's not really good evidence for multivitamins and minerals or for antioxidants. Now it's not to say that there's not certain antioxidants and that multivitamins, minerals are not important. If you've got nutritional deficiencies, which is a big issue in lots of areas of the world, they can be extremely important and save lives. But in our affluent society, probably no difference for health outcomes that matter, it's it.
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And that makes me think of two things. Number one, the health outcomes that matter. Nutrition medicine is so dynamic, so complex. For example, the outcome of mortality is important to some people. And for me, I might not want to lose my hair. So I might need, right, so I might need, you know, my mind. Okay, well how do I make sure that my vitamin mineral status is optimized to make sure I have enough copper and biotin or any of these various nutrients?
- [38:24]
Yeah, fair enough. But then if you actually did experimental studies of biotin, what do they actually show? I don't know if there are any, but biotin is, we know it's, I think, I guess, rich in skin and nails and hair. I might be getting something wrong here. And so we make an assumption based on our understanding of physiology. But it doesn't actually mean that if you take biotin that you're going to not lose your hair, you're going to lose less hair. We need to know that from a well done experimental study, ideally a randomized control trial. I don't know if there's any that have been done, but there's all kinds of examples where we think we have all kinds of ideas based on what we understand about physiology. But then experimental studies come along and it shows something different.
- [39:13]
That's a very good point. Is that, do you think that that is a challenge for providers? And I don't want to say just clinicians because it's not, it's really everybody. This is, it's our health. Are nutritional type studies challenging to do?
- [39:32]
I would say yes, very challenging. But first of all you have to say what type of nutritional studies. So if you're doing a, if you get funding to do a study on supplementation versus no supplementation or versus placebo, it's basically like doing drug trials. It's not near as complicated. But if you are doing a study, let's say in a clinical trial on dietary programs, well, it's not a supplement that you can use a placebo and the antioxidant supplement looks the very same as the placebo and you can blind the study on multiple levels. If you're doing dietary programs, people know what they're getting. So right away there's going to be some limitations in terms of the inferences that you can potentially make.
- [40:23]
Do you think that if you could wave a magic wand, I'm sure that we have some up in my kids rooms, we have all sorts of magic wands and things of that nature for an understanding perspective for the listener. What do you think would be critical for them to, I would say understand about this landscape of evidence based practices and thinking about it where you could say, okay, I'm going to correct your way of thinking and interpreting this.
- [40:55]
Dr. Gabrielle Lyon
There you go.
- [40:55]
Dr. Bradley Johnston
I've just now anointed you like so some, some tips for the biggest misconception, the biggest challenge of, you know, again, we throw these terms around all the time. Evidence based practices, evidence informed. But is it really evidence based? Is there, you know, you have highlighted with your work which has been absolutely tremendous, you've published almost, I don't know, 200 peer reviewed papers really at the forefront of nutritional sciences in various aspects, tackling all kinds of questions. Because I think your passion has been asking a question and then examining the evidence of the things that we think that we know, right?
- [41:43]
Yeah. Well, so I would say, Gabrielle, what would I say? Well, so you talked about evidence informed and of course, evidence based, I would say we're all trying to help people. We're all using evidence to inform. I think our practice, if you're a clinician or a public health person or a researcher. But to me, I kind of make a distinction. Evidence informed is using evidence, but it may not necessarily be systematic up to date evidence or systematic up to date and high quality. So we're all evidence informed. But lots of times people say, oh, it's evidence based, it's evidence based. I think lots of times it might be better, better to say, well, that person's evidence informed. But if you want to be more geeky and nerdy, evidence based practice or philosophy is these three central tenets and then understanding the competencies. And then I think if you're in the space of doing applied human research, for example, it's having a strong understanding of research methodology and doing the, you know, doing high level study methods to try and answer the questions that we, we have uncertainty about.
- [43:01]
And you had mentioned the quality of evidence, those high, moderate. How many categories is high, moderate and low? Is there a gray in between?
- [43:11]
Yeah, so I think, well, maybe I'll, I'll talk a little bit about grade. Exactly where a grade approach or grade methods. So grade is a part of evidence based practice. It's really, you know, the sophisticated part of evidence based practice in some ways. So grade does two things. First, it's a method that we use when we're producing systematic reviews with meta analysis. And so by the way, a lot of people just use the term meta analysis. And I always say, I don't care about meta analysis. I want to know if it's first based on all of the, all of the evidence. So is it a systematic review with a meta analysis?
- [43:50]
And what are those things?
- [43:52]
What are those things? So it's if Matt wants to know if you have a clinical question or a public health question and you go out and you do a systematic literature search to find all of the evidence, whether it be randomized trials or non randomized studies, like cohort studies, and you bring together all of the evidence on your given question and you essentially have a team of people screen the articles independently. They do data extraction, they do risk of bias assessment, and then they assess the certainty of evidence using the grade approach. So going back to grade, if I could. So grade is a method to, when you're doing systematic review with meta analysis, you basically assign a certainty of evidence for each outcome on an outcome by outcome basis. So, and it can be high, moderate, low or very Low. So there's four categories that answer your question and there's a whole bunch of questions that go into determining what the certainty of evidence is. And there is some subjectivity to grade. People have criticized grade because some claim that it's subjective. Would say that there's over 40 studies that have been published on the grade methodology. It's been around for 20 years. It's based on a group of methodological people from around the world. And so there's a ton of merit to grade. Is it perfect? No. But one of the goals of grade is to be transparent about how did you arrive at moderate certainty evidence?
- [45:35]
Dr. Gabrielle Lyon
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- [47:17]
Dr. Bradley Johnston
Like when you looked at the risk of bias when you looked at issues of potential imprecision, et cetera. So making copious transparent notes within your research reports about how you arrived at the certainty of evidence. And another group, somebody else that wants to use your systematic review, they might say, oh, I don't think the certainty of evidence is moderate, I think it's high or I think it's Low, that's fine, they can disagree. But doesn't it take away and it should create conversation and transparency rather than black box kind of science.
- [47:48]
The way that I'm hearing it is it actually should be somewhat unifying because, you know, I'm looking at this article right now and we can link it, I want to make sure this is open access, this is grade evidence to decision frameworks and it's a systematic and transparent approach to making well informed healthcare choices.
- [48:09]
Yes. Yeah. So the evidence, the great evidence decision framework is what we use and follow in order to make our recommendations. So it looks at the totality of evidence, on benefit, on harm, the certainty of evidence values and preferences. Eve has questions on cost, on acceptability and feasibility of potential interventions that you're looking at. So it's a way to move from the body of evidence like a systematic review with meta analysis to a recommendation for patients or the public.
- [48:45]
May I ask your opinion on something?
- [48:46]
Sure.
- [48:48]
Why do we care about this?
- [48:51]
Why do we care about grade or evidence decision frameworks? Is that.
- [48:54]
Yeah, both. Because I think that there's one. This is a personal question and I can go first if you want me to, but why do we care about using a grade methodology first and then secondly, why do we care about evidence based practices?
- [49:12]
Yeah, well, I think that's a really good question. So grade has been adopted by I think now over 120 organizations worldwide. So WHO, CDC, Cochrane, Joanna Briggs Institute in Nutrition. The American Academy of Nutrition and Dietetics uses it to inform its evidence analysis library, which they do systematic reviews and guidelines. So it's good to have a common standard across health sciences. Right. So whether it's surgery or medication or nutrition, we're comparing apples with apples.
- [49:50]
I totally agree with you and actually you were the first person that I, when I started reading some of your work, really brought because yes, I'm a clinician, yes, I'm a physician, but I'm very interested in the impact of our choices from a nutritional aspect. I mean that was my first love and it was very fascinating to read some of your papers using grade analysis. And again, this grade system, which has been used by hundreds if not thousands of people, but it was, it was quite helpful and it laid out a framework to help me personally evaluate evidence. And so I, I think that there's a ton of benefit from it. I don't know if there's something you want to add there.
- [50:39]
Yeah, well, and so the, and the main benefit is if you as a clinician are looking at systematic review evidence to Inform your practice. You can say, okay, there's moderate certainty or there's low certainty and that can help inform your. And then the second component of grade or GRADE approaches is the methodology like we've talked about a bit to move from systematic reviews to recommendations or making strength of recommendations. So exactly as you pointed out, Evidence decision framework. So grade is, you can kind of think of it in two different categories.
- [51:16]
When you are thinking about the decision making process. And you know, we talked about meta analysis, systematic reviews. Are there ways that people could pick out what a good systematic review is?
- [51:34]
Yeah, there's definitely, there's tons out there. Yeah. There's tools available to us to determine the quality of systematic reviews. So the, the one that's used most is called amstar. I forget what the acronym stands for, but it's out of the University of Ottawa. Beverly Shea, you Canadians and there's also something called robis which was developed by the Cochrane Collaboration. So there are two instruments that can be used to determine the methodological quality of systematic Reviews. Amstar has 16 questions that you have to go through and there's also things like jama, user's guides to the medical literature and what we've produced, the nutrition users guides to the, to the nutrition literature essentially. And there's, we have guidance available to help people make sense of systematic reviews.
- [52:28]
Do you think that this, and again this is more of a personal question in terms of your personal opinion. Do you think with the influx of information, I mean you are very well trained. Do you think that there is benefits and challenges with all the information that has been coming out, if we don't have a, a structured way of examining it and I can ask that in a different way.
- [52:56]
Yeah, well, I think I know what you're driving at. You definitely need a common structure, otherwise people's biases get in the way. There's a whole field of cognitive biases and, and even scientists are very good sometimes at having biases that they may be unaware of. Right. There's something called the sophistication effect. It's a cognitive biases where smart people can explain away their answers. Right. So yes, we need common structures to answer clinical and public health questions and make guideline recommendations. Otherwise in a transparent structure, otherwise it's hard to have conversations and reach consensus.
- [53:44]
Is there a way that someone could. Well, I guess even to back it up. Why does it matter so much to you?
- [53:55]
Why does it matter to you? Well, I was kind of trained in evidence based practice and health research methods and, and it's a Passion. Because it's a hard question. Why does it matter so much to me? Well, it matters because we're trying to help people. Okay. And we want to help people make informed decisions. We want them to understand if they're so inclined. There's lots of people. I'm sure you had lots of patients. They just say, you tell me, Doc, but there's lots of patients and families that would love to know what is the best available evidence and can you help me understand it if I take this drug versus I do a behavioral intervention versus surgery. Right. So I think about the Canadian pediatric obesity management guidelines. We've done systematic reviews on all of those topics. And the goal is, when it's published is people can make more informed decisions about all of the outcomes that we've summarized. They can choose the outcomes that matter most to them and get a sense of what the risk reductions are and the certainty of the risk reductions and the potential harms, rather than, for example, the expert or the clinician driving that decision. Always. I don't think that that's necessary. It's obviously a great idea if you're in acute care medicine, but it's not a great idea for managing chronic disease.
- [55:25]
I think it's extraordinary. I think that. But it. Again, we often have scientists come on and discuss their randomized control trials and their mechanistic data. But what I think that you offer, which is absolutely extraordinary, is a way of thinking about something to get a particular answer. Whether you 1 likes an answer or not, it allows us to. To our best capacity. Number one, I am hoping, which I think you and I both agree, it is unifying. It is not divisive. It is a way of saying, okay.
- [56:04]
Dr. Gabrielle Lyon
Here are my biases.
- [56:06]
Dr. Bradley Johnston
I think this nutrition plan is the best because I grew up on a farm or X, Y and Z versus someone else grows up, I don't know, in New York City, that by creating a framework and an architecture, we can actually begin to have unified rather than divisive conversations. Again, to set the framework for conversations to ultimately make good choices.
- [56:36]
That would be ideal, optimal.
- [56:38]
Yeah. Is there. And would you say that as people are going through grade. And again, this is a framework for thinking about. Maybe thinking is not the right word. A grade work, a framework for evaluation. Is there places where it is really excellent, for example, pharmacology or the questions that we are asking.
- [57:08]
Dr. Gabrielle Lyon
So grade is exceptional at.
- [57:10]
Dr. Bradley Johnston
And I'm just throwing this out there, evaluating if a statin is going to reduce all cause mortality or grade is exceptional at determining, for example, I've had many patients ask me about rapamycin. And as I'm thinking about this, I'm thinking, okay, well, I can use. And I understand that this is somewhat of a technical episode, so we'll probably follow it up with maybe taking someone through the process, because I should go through this process myself as I'm looking at, for example, rapamycin and determining what is the best available evidence.
- [57:43]
Yeah.
- [57:44]
Or nutrition is grade. You know, where can we think about where grade is excellent versus maybe it's excellent across the board?
- [57:55]
Yeah. Well, there's. So there's been debate about is grade applicable, is it optimal for the. In the space of nutrition? And I believe, we believe that it, it is. And nutrition is complex. Sometimes, as we've talked about, when you're doing grade or using grade, it's very important to be working with nutrition experts to make sure that you, that you understand or the group has an understanding of the nutritional intervention and maybe the biochemistry under it and so forth. So that when we're doing the certainty of evidence on an outcome by outcome basis, that we're not missing something. Right. So grade has a. There's a domain called I won't go into nitty gritty, but there's a domain called indirectness, which essentially means if there's issues of indirectness. So if you have animal model data and you're trying to make a recommendation for a patient, you have an indirectness.
- [58:53]
Issue, which is a challenge all the time.
- [58:56]
Right. So you. Using grade, you would probably rate the certainty of evidence down. So you might have a body of randomized control trials, but they're all rodent model studies. But it's the only data that's available for the clinical question you're trying to resolve. Randomized trials using grades start at high, but can be rated down for different issues, including indirectness. So you would definitely write down at least one level or probably two or three levels because you only have animal model data. So it would quickly go from high certainty, even though it's based on a systematic review of randomized trials, probably to low or very low because of this indirectness issue.
- [59:41]
And when you're rating the certainty of evidence from a translatable perspective, obviously you want it to be high or moderate, but is there a way that it balances out and I don't know, maybe you have an exact example. You know, I have a handful of papers here. But if, for example, you ask a question and you've got the results based on grade are you have high certainty of evidence and you're trying to go to an answer. Does statins improve all cause mortality?
- [60:16]
Dr. Gabrielle Lyon
And then by what number?
- [60:17]
Dr. Bradley Johnston
If someone. If you are looking at the totality of evidence, because again, there is so much information out there for both clinicians, patients, armchair researchers, it's. It's bananas.
- [60:30]
Yes.
- [60:31]
Right. It's only followed in the bananas level of the amount of cartoons that are coming out. It is crazy.
- [60:37]
Well, that's the other thing is evidence based practice is kind of hard work. You have to, you know, to keep up with the literature. When in a kind of banana type atmosphere, it's smoothie way.
- [60:47]
Yes.
- [60:47]
Yeah.
- [60:49]
How would we. Is there a formula for collectively understanding what that outcome is? So you've got some things that show the certainty of evidence is high, and then you have a handful of things that show the certainty of evidence is moderate to low. Is there a unifying formula to say.
- [61:13]
Dr. Gabrielle Lyon
Overall based on all of the data.
- [61:16]
Dr. Bradley Johnston
There is a moderate level of certainty that statin use decreases all cause mortality by 18 is making it up.
- [61:26]
Yeah. So I'm not exactly sure how to answer your question. What's the specific question?
- [61:37]
Well, as I'm thinking about guidelines, right. As these guidelines are coming out, it's challenging from my perspective and I can just speak for myself. So I am thinking about the upcoming 2025 Dietary Guidelines. Me personally, I issued a statement about my position on it. And I know that Dr. Donald Layman and a handful of other people of my colleagues have issued these statements and these guidelines will come out and there obviously will be various components to these guidelines, whether it's protein, whether it's saturated fat, that. How can we think about the certainty of evidence when something goes into a guideline and it doesn't have to be the dietary guidelines, but basically because there is the. You said the values and preferences, right? So we have values and preferences. Am I a good student? Yes.
- [62:34]
Yeah. Very good student. Yeah, yeah.
- [62:36]
So we have values and preferences. And then collaboratively we get together or individuals get together to say, okay, these are the values and preferences based on this, the certainty of evidence for this recommendation. I'll say for me, 0.8 grams of. 0.8 grams per kilogram of dietary protein is, I don't know, the minimum amount to support healthy aging. That certainty of evidence could be, I don't know, moderate to, or maybe it's low.
- [63:15]
Maybe there's evidence and it's low and people are willing to embrace the uncertainty that we don't really know. And that's okay. I think sometimes people are fearful of low or Very low certainty evidence. So when I talked about grade to make to do strength of recommendation. So our recommendations when we follow grade are either strong recommendations or they're conditional.
- [63:42]
Dr. Gabrielle Lyon
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- [65:31]
Dr. Bradley Johnston
Strong recommendation can either be for or against an intervention, as well as the conditional recommendation can be for or against. A strong recommendation basically means just do it. There's very compelling evidence and most patients are members of the public. Public, they value the intervention. The trade off between benefits and harms is, is. It's much in favor of benefit and we can make a strong recommendation.
- [65:58]
Could you give me an example of that? Would that be like, you should get a colonoscopy at age 50 or 45? Would that be, you know, I mean, I'm just making this up.
- [66:08]
Yeah, no, I. Well, right away I'm thinking, I don't know what the evidence is for that, but I know there's been controversy probably, at least in things like prostate and breast screening and so forth. Yeah.
- [66:20]
Or something that you can think about that maybe is just. And so the reason I'm asking this question is because as we frequently have these very scientific conversations with various experts, this now provides. Because you have agreed to be a guest, this now provides just a way of thinking about the framework differently. Meaning are there certain things that we can evaluate that we definitely know that we should all be doing?
- [66:48]
Yeah, well. So I can use an example from managing obesity, whether it's adults or children, I think generally we tend to make a strong recommendation for multi component behavioral intervention. So if you meet criteria for obesity and especially if you've got your lipids are off and we know it's an important risk factor for early mortality or early chronic disease disease, we can make a strong recommendation. We'd have to look at a specific situation, but strong recommendation for multi component interventions. So diet, physical activity, maybe kind of psychological support or group support, behavioral support. That would be perhaps an example of a strong recommendation. I don't know what the recommendations are on statins, but I'm sure that there's strong recommendations for certain patient populations in like up to date would probably give guidance on that, I suspect.
- [67:52]
And is there a unifying agreement? For example, is there a qualification that's something that is required for a strong recommendation?
- [68:04]
Yeah. So generally, using the great approach, we make a strong recommendation if the certainty of evidence is high and all or almost all patients or members of the public value that trade off between benefits and harms.
- [68:25]
It's really fascinating when someone is going through the process of understanding the evidence. Are there things that potentially are, I don't want to say simple to understand, but this idea of randomized control trials, could a people will say the quality of evidence from a randomized control trial is the gold standard. Right. And again, this is maybe.
- [68:55]
It depends.
- [68:56]
So this is what I was asking people.
- [68:57]
Did the trial with rigor and, and reproducibility?
- [69:03]
That was my question.
- [69:07]
So what's the specific question?
- [69:11]
As we examine the quality of evidence and we discuss it by saying, here is a randomized controlled trial, here's whatever cohort study or case control study, there is a variation. How about this? Is there a variation as to the quality? Even if something is a randomized controlled trial, as we're examining the evidence, as we are trying to create a framework for men, women and children that are listening to this, physicians that are listening to this, is there a variation in the quality of what we consider high quality data like a randomized controlled trial?
- [69:51]
Yeah, there's definitely variation in terms of how well people do studies. And I think it's important to remember that when we're talking about grade and certainty of evidence. This is applicable only for systematic reviews with meta analysis. Right. If you're just looking at a single study. Well, we know, like from the hierarchy of evidence that randomized trials tend to give more reliable answers than observational studies. But we can assume that because there's one randomized trial that we have high, that shows a. A favorable outcome for outcomes that matter to patients. You can't assume that that's high certainty evidence. There could be other studies that have been published that you've missed. So I'm talking really from the application of grade is at obviously an evidence synthesis level. And the other thing that I thought might be worth talking about is most recommendations that are made using the grade approach are conditional, meaning we don't have great evidence. And there's nothing wrong with conditional recommendations. It was Grade previously used the word weak recommendation. And people. Grade eventually learned that people don't like the idea of a weak recommendation.
- [71:06]
Wait, wait, what do you mean? What do you mean? Weak recommendation? Can you say that again? I just.
- [71:10]
Yeah. So when grade. Up until just a few years ago. So the language that grade was using was mostly strong versus weak recommendation. But they've decided as a group to use conditional rather than weak because a lot of people were uncomfortable with making a weak recommendation for maybe an intervention that they've been using for years. And, you know, it puts people in a somewhat uncomfortable position. But I think what's important to understand is, okay, conditional recommendation basically means the evidence isn't great. Values and preferences differ. Like some patients will take it, or some members of the public will be interested in following it and others won't. And it should be. Ideally, they should be informed. It should be shared decision making. There's nothing wrong with that. And if we did that more often, maybe in the space of nutrition, maybe there's less room for walk backs like the example of antioxidants. Eventually we realize that there's no good evidence for taking antioxidants to reduce cardiovascular risk.
- [72:15]
It. And I, I will say that I'm just looking at the history of the meta analysis. It. The word meta analysis was coined in 1976.
- [72:26]
Yes.
- [72:27]
Dr. Gabrielle Lyon
Not that long ago.
- [72:28]
Dr. Bradley Johnston
I forget his first name. Gene Glass.
- [72:31]
Yeah, Gene Glass. And who stated meta analysis refers to the analysis of analyses?
- [72:40]
Yes, the anal. Yeah. So analyzing multiple studies. Yeah.
- [72:45]
Which I think the statement that you brought up about it. It's okay, it's. There is again, there's a lot of emotion involved with people's health and maybe it's within all spaces. I'm just not I mean, I don't know. Do people in physics argue about this kind of thing? I'm not entirely sure. Or maybe in electricity, I don't know. But whether something is weak or strong, if there's a way to remove some of the emotion behind it, then it's okay. If it's a weak recommendation and you choose to follow it.
- [73:25]
Yeah. I think another important component is I think some people that maybe have a perception that if you only have observational studies for a public health question or a clinical question, then automatically it's going to be a weak or conditional recommendation. Automatically the certainty of evidence is low. That's not necessarily always the case using the grade method. So some people might be familiar with the old school static hierarchy of evidence where at the top were systematic reviews and meta analysis of RCTs and after that was systematic reviews of observational studies. And below that was rct, a single rct, single cohort reports. Grade is a sophisticated approach to. It's kind of starts to some degree with that hierarchy. But the evidence can move up or down depending on a whole bunch of questions we ask of the body of evidence. So there are examples of observational data only that move up from low to possibly even high certainty evidence. So the example that most people would be familiar with is smoking and lung cancer. Cancer. Right. We don't have randomized trials of smoking and the risk of lung cancer, but we have a lot of observational data and we have observational data that shows large exposure effects and a very clear and reproducible dose response curve. So with that observational data, which has its limitations, we do have high certainty that smoking is a problem when it comes to risk of lung cancer.
- [75:06]
You created a website. It's evidencebasednutrition.org can you tell me a little bit about it and why you created it? It's actually phenomenal. We'll put a link to it. But why did you create this and how can someone utilize this?
- [75:25]
Yeah, sure. So we created it a group of us who kind of work together regularly. A lot of people that have kind have come through McMaster University, the home.
- [75:36]
Of evidence based practices.
- [75:39]
The home of evidence based practice. Well, I mean a lot of people I guess have websites now. It's a resource where we kind of park materials to help people interpret the literature like our nutrition users guides that we're starting to publish.
- [75:56]
Yeah, I saw that.
- [75:58]
We talk about some of our guideline work on the website and yeah, it's just a home to really promote evidence based practice in the Field of nutrition. Because my sense is it needs some uplifting.
- [76:15]
Yeah, I think that you're absolutely right. And it's the one thing that everybody does. We all eat. And just being able to understand and sift through the things that could potentially have high quality evidence, like probably eating.
- [76:32]
Dr. Gabrielle Lyon
Fruits and vegetables, maybe.
- [76:35]
Dr. Bradley Johnston
I'm curious.
- [76:36]
I've never looked at that question, but we probably have mostly observational studies and it's what fruits and vegetables at what dose?
- [76:47]
I mean, this is just highlights the complexity of the question of how do you think that it is more challenging to do nutritional research than maybe other domains of research? For example, you studied kinesiology.
- [77:02]
Well, if you're doing like dietary programs, it's very hard because people know what they're getting. You can't blind it. People can. They're kind of typically done in free living environments. Although of course there are feeding trials that are. You've done feeding trials or pests? Yeah. Were today challenging.
- [77:22]
Oh my gosh. So there was again. You can only keep people in a metabolic ward for so long. We've done at the University of Illinois. I did. Where we fed them all their meals. We would pack everything and they would show up.
- [77:34]
And they were expensive too?
- [77:37]
Very expensive. Yes.
- [77:39]
Yeah, yeah. And unfortunately, as I understand it, a lot of those metabolic boards are kind of drying up and there's not a lot of funding to keep them going, which is really sad because there's still a lot of work to do in this space. And I'm a huge believer that we need more randomized trials in the space of nutrition because there's a lot of controversy, there's a lot of areas that we really have uncertainty about. And the only way to answer some of these questions, not all, because there's limitations with randomized trials, of course, is to do. To do the trials. And I can talk about examples.
- [78:17]
Yeah, I would love you to. Please.
- [78:19]
So the systematic review that I mentioned earlier that we published in the British Medical Journal led by Georgio Koram, who's currently a medical student at the University.
- [78:30]
Of Manitoba, was this the evidence based practice competencies?
- [78:34]
No, this is BMJ Systematic Review Network Meta Analysis of popular diets for cardiovascular or for reducing mortality and cardiovascular outcomes. Okay. So I talked about seven randomized trials that measure all cause mortality. Only one of them. All of them are mostly. Most of them are in Europe, I should say. And the biggest ones that people might be familiar with are PREDIMET, almost 7,500 people randomized. So that single trial is probably driving the effect size To a considerable degree, there's only one randomized trial of a Mediterranean style diet in patients that have cardiovascular risk in the United States.
- [79:26]
1. I want to just repeat that there is one randomized control trial, only one.
- [79:31]
And it shows basically no important effect when it comes to reducing all cause mortality, like trivial to no effect. So we should be doing. There's a Food is medicine research initiative now by the American Heart association and others. We should be doing Mediterranean style dietary interventions for these patients and comparing it to the, you know, the, the either low fat type intervention or whatever the typical standard of care is. A second example is you might be familiar with salt substitutes, low sodium salt substitutes. There's some really compelling randomized control trial data, mostly out of China, that shows important risk reductions in stroke and mortality.
- [80:22]
Is this with potassium chloride type?
- [80:24]
Yeah. So normal table salt is like a hundred percent, 100% sodium chloride, but you replace some of that sodium chloride with potassium chloride. Exactly like 25% of it, based on some of the Chinese studies. And we're showing important risk reductions, absolute risk reductions, with I think probably a moderate certainty evidence level. But there's only one randomized trial again that's been done in the United States or in Canada, and they only measured surrogate outcomes like blood pressure. They didn't measure mortality, if I'm not mistaken. And the study is quite old, I think it might be 20 years old now or more. So we need to do the trials here in North America to see if we can reproduce these studies and to help determine the certainty of evidence after we do experimental studies or more experimental studies.
- [81:26]
And are some of the challenges getting, for example, students? You run a program at Texas A and M is, is part of the challenge getting students, people interested in. Do you run a PhD program, master's program. Can you tell me a little bit about the, the program that you're running?
- [81:45]
Sure.
- [81:45]
Yeah.
- [81:46]
Yeah. So I don't run it. I just, I'm a.
- [81:48]
Dr. Gabrielle Lyon
Maybe you're going to be up for dean.
- [81:50]
Dr. Bradley Johnston
Who knows?
- [81:51]
I'm a professor and associate professor there and I've got grad students, a number of PhD students, and we don't do randomized trials. We do a lot of work in evidence synthesis, systematic reviews, primary studies on values and preferences. I think we need a group of trialists that are in the space of nutrition, that come together and can work together to ask some of these important questions and do rigorous, high quality randomized trials. But there needs to be funding, not necessarily within nutrition. I think you can get funding from different NIH Groups, you just need people that have that nutrition expertise and clinical trial expertise, methodological expertise to come together as a team and to write those research proposals and try to get them funded.
- [82:53]
Are there less of those individuals?
- [82:55]
I think so. I mean, I don't know systematically, but that's what I kind of hear or see on social media. But I think we need more experimental studies and we need to train people more.
- [83:08]
The next generation. Yeah, ideally, the landscape seems to be changing in the way and again, this is just from my perspective that more people are moving towards various other avenues of exploration that maybe are moving a bit away from science and actually doing higher education. Again, I only hear this from my colleagues that it is more difficult to recruit students. It's more difficult the interest in science, while I think we're in a very privileged space where we are very interested in it, the listeners. And by the way, I love you guys. I, I do this because I, I believe so wholeheartedly that collectively we can make a difference that you know, people are going to various careers being a Instagram star or just it's. The landscape is changing. I think that the importance of very specific cognitive processes and, and rigor has, has changed. The importance of it seems to have changed. And you know, you talk a little.
- [84:19]
Dr. Gabrielle Lyon
Bit about, I've heard you refer to.
- [84:21]
Dr. Bradley Johnston
Quote this kind of scientific mindset.
- [84:25]
Yeah, the scientific mindset. Well, all of us as scientists, we endeavor to have that and I think we probably all have different definitions but when I think of that I think of curiosity, intellectual curiosity about questions about staying open to the data. I think about being agnostic to the data, especially if you're doing guideline work or doing systematic review work. It takes also, I think a bit of bravery to be agnostic and to be open minded and stay curious. It's like, like we all are human beings and we've got our cognitive biases. So I can tell you maybe a story of my own cognitive biases that I probably remember for many years is not that many years ago. We were doing a systematic review, meta analysis on again dietary programs, but not for mortality, but for cardiovascular risk factors like blood pressures, cholesterols and weight. And we found 14 different dietary programs across 100 and I think 20 some randomized control trials. This is also, I think in, it was published in the, in the British Medical Journal and low fat diets did quite well. They were in like the top five or something. And this is probably going back five or six years ago. I said to my mentor, Dr. Guide, I said, said I'M kind of surprised about low fat, you know, maybe like should we call it something else or. And he, I, he said to me the data is the data. And that's, that was the end of the conversation. So it's hard to stay curious, I think. And I now do not take any funding from industry. I don't. It's not because I believe it's bad. I think you can do very rigorous, important work with industry funding and usually industry is involved in supporting randomized trials, for example, to some degree, paying for the intervention, paying for refrigeration. But because I'm in the space of doing evidence based practice and guidelines, it's best to just avoid any misperceptions.
- [86:53]
Yeah, you know, I've, I've never spoken about this before, but one of my goals this year is to create a non for profit that a portion of what the podcast generates a portion of. You know, eventually I would love to create a supplement and these are things that I feel very passionate about that we take a portion of that revenue and we put it back into evidence based practices for research. So that is on the docket for.
- [87:27]
That'll be wonderful. I'll be sending you emails.
- [87:30]
So that is, you know, just, I think as we do better and we build and we educate the public, that should go back, funds should go back into research. So that again, I've never talked about it, but it's something that I'm, I feel very passionate about because we do have to evolve it. Where do you think, if at all, do you think AI is going to be helpful in this landscape?
- [87:57]
Definitely, yes. It's a part of the landscape already. I tell my students that AI can either be your competition or your research assistant. Better to make it your research assistant. So we need to keep up with our developed skills and how to use it. When it comes to evidence synthesis, there are tools now that we can use to screen studies. There's still a lot of room for improvement. Moment. But it's definitely. I know of colleagues in Australia who do a lot in the space of evidence based medicine practice and they've been, I forget the name of their kind of group, robot reviews. I think in Australia, if you look up Paul Glasio, they work with AI tools. They've been doing it for over five years to, to create systematic reviews. But one of the main lessons they've learned is you actually have to have a methodology just at the center of the review all the time to make decisions. And if you do, it's very helpful. And I think they've done reviews in something like two weeks where we're working with AI and working with methodologists to make decisions along that pathway. So there's. Yeah, there's. I don't know a whole lot about the space of AI and systematic reviews, admittedly, but I do believe that it's an important part of the future, and it's already here, and I probably have to work on my AI skills a bit Same.
- [89:33]
But it sounds also that we still need cognitive manpower, that computers are or AI and some of this technology we still require scholars, scholarly activity, critical thinking, and just ways to further advance the science is.
- [89:55]
Yeah. And I think hopefully we need humans at the center of science. Like, once AI is being done only by computers or, sorry, science is being done by computers in certain domains. That's kind of scary. There needs to be a lot of transparency and reproducibility to everything that's done and where you have your data open for investigation, if it's created in part or in large by different AI tools.
- [90:28]
Well, Dr. Bradley Johnston, I'm so grateful for you sharing your time and your wisdom. The work that you do is tremendous, and it has been extraordinarily helpful for me, and I know many of my colleagues and many others. So thank you so much for joining me.
- [90:45]
Thanks for having me. Dr. Lyon, it's been wonderful.