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Jonathan Wolf
Welcome to Zoe Science and Nutrition where world leading scientists explain how their research.
Jenna Machoke
Can improve your health.
Jonathan Wolf
In the last two years there's been.
Jenna Machoke
A surge in Google searches containing two immune boost. And what's followed has been a wave of brand new products, detoxes, supplements, superfoods, all claiming to provide this potentially life saving immune boost. But what does boost actually mean?
Jonathan Wolf
Is it even possible? And could our desperation for a quick fix be doing more harm than good? Dr. Jenner Machoke joins us today to.
Jenna Machoke
Separate fad from fiction. Jenna is a senior Lecturer in Immunology at the University of Sussex, an author of the Science of Staying well and your Blueprint for Strong Immunity. You'll leave this episode with an evidence based approach on how to support and maintain a healthy immune system. Jenna, thank you very much for joining me today.
Dr. Jenner Machoke
Thanks for having me, it's great to be here.
Jenna Machoke
So we have a tradition here at Zoe, which I think we might have warned you about, where we always start with a quick fire round of questions from our listeners. And this is designed to be super hard for professors, but because you are only allowed to say yes or no, or if you absolutely have to, you can give us a one sentence answer. Are you willing to give it a go?
Dr. Jenner Machoke
Yep. Let's go.
Jenna Machoke
All right. Can I improve my immune system without taking drugs?
Dr. Jenner Machoke
Yes.
Jenna Machoke
Is the immune system mainly to fight off illness?
Dr. Jenner Machoke
No.
Jenna Machoke
Should you try to boost your immune system?
Dr. Jenner Machoke
No.
Jenna Machoke
Will taking vitamin C supplements reduce my chance of getting a cold?
Dr. Jenner Machoke
No.
Jenna Machoke
Can my emotions make me ill?
Dr. Jenner Machoke
Yes.
Jenna Machoke
And last one, you can have a whole sentence. What's the biggest misconception about the immune system?
Dr. Jenner Machoke
I'd say that if you get sick, you know, we're going into winter, seasonal viruses are around. If you get sick, it means you've got a rubbish immune system.
Jenna Machoke
Well, you know, that's brilliant because that is literally what I wanted to start this with. So I was thinking about my experience when I was a kid. Both my parents are complete workaholics, but the setup was also quite traditional. So my mom was always the person who would pick us up from school. She was also sort of looking after us. And I remember like every few months, basically my mom would just sort of collapse at the end of the day or when she came back from work, like go to bed, she's like, I feel really terrible. And for 24 hours she'd be wiped out and then she'd sort of pick herself up and keep going. And my dad basically never got sick. So when a virus hits our house, you know, everyone in the family gets it. You know, I've got children as well, and my wife, who's a doctor, she gets a little cold. She says it's nothing, and she just keeps going. And I often feel like I'm wiped out. It's like five days until I feel like I probably got better. So I'm just basically really curious around, you know, have I just inherited my mother's terrible immune system? How much of this is about, like, the stress that I know that, you know, I put myself under and that I feel. And so I'm really hoping that you can unpack this for us and at least I will learn something. But I'm hoping some of our listeners have some similar sort of anecdotes from their lives.
Dr. Jenner Machoke
I think that's something that all of us can relate to. And it also speaks to how complicated the immune system is, because you've hinted a little bit about genetics. Is it that I've just inherited this? He hinted a little bit about stress. There's also gender differences in how we respond in terms of our immune system. And there's the exposure piece. So we often tend to think it's our immune system's rubbish. We've got sick. Oh, my goodness. But it also comes into play to this bigger equation of how much exposure you get, perhaps because your mom was the sort of primary caregiver of children. Like, she's getting more exposure to kids. Kids are little germ factories, because the sort of basic hygiene is sometimes a work in progress, that is for sure. So, you know, that's part of the equation. Genetics are part of it. So you will have inherited immunity genes from both your mum and your dad. Now, the interesting thing about the way that we inherit those genes is that you will get a set from both mum and dad.
Jenna Machoke
Jenna, before I dive more into that, I want to pull us back for a second because we're already talking about the immune system, but actually, I don't understand what the immune system is at all. It's like one of those words that I use, but I don't understand it. What is it?
Dr. Jenner Machoke
It's hard to grasp. And we talk about it as one thing. And if I asked you to say, where is your digestive system? You could probably point to the location on your body. If I ask you to point to where your immune system is, you might not know where.
Jenna Machoke
I'm literally like, I don't.
Dr. Jenner Machoke
Yeah. But that's because it's everywhere, from your brain to your big toe, it's absolutely everywhere. And that's because Essentially, it's helping keep your body safe. So it has to be everywhere. It's really enriched at the barriers to our body. So, you know, under your skin, because that's exposed to the environment. The lining of your nose, the lining of your mouth, all the way down your digestive tract, you have huge numbers of immune cells that are fortifying those barriers, because those barriers are very delicate. So the airway lining and the digestive tract lining, they're very delicate. And that serves a function that helps us exchange oxygen when we breathe. It helps us digest our food and absorb nutrients. But we need to have that extra fortification because that's vulnerable. You know, we can inhale germs or swallow germs, and that could make us sick. So you will find immune cells everywhere. They're also swimming around in our blood, so they're performing a kind of surveillance function. And then you have immune organs where they'll, like, congregate and certain functions. So we have lymph nodes which are all over our body, and they're all connected with the lymphatic system that's kind of like your blood circulatory system, except it doesn't rely on the heart to pump it around, so it relies on your muscles moving. And the lymphatic system is going to squeeze those immune cells around, allowing them to circulate all over your body. And they pass in and out the lymph nodes, and that's a place where they can meet and talk and do various functions.
Jenna Machoke
It's a beautiful picture. I'm starting to think about all that's around me. You've mentioned the word immune cells quite a lot when I've asked what is the immune system? Is the immune system like a set of immune cells?
Dr. Jenner Machoke
Yeah, immune organs, lymph nodes, spleen, bone marrow, and the molecules that they're producing to communicate with each other. So you've got cells, molecules, and then organs.
Jenna Machoke
I think we all know that it's got something to do with dealing with viruses and bacteria and things like this. But I think at that point, most of us are drawing a big. Could you help us understand a little bit more what it does, how it works?
Dr. Jenner Machoke
It's hard to conceptualize because it is this kind of galaxy of things spread out throughout our body. But within this collection of immune cells that I've mentioned that are swimming around in your blood and lymphatics, congregating at all those body barriers, there's many different flavors of immune cells, and they each have their own specific set of functions. And Then they'll collaborate with other cells to do certain jobs. Because if we think about it through the lens of infection, there' different types of infection. Viruses look different from bacteria, which look different from parasites. So we have, over the evolution of the human race, developed all these different immune cells to try and cope with the multitude of different infections that could try and get in our body and harm us.
Jonathan Wolf
Let me tell you a quick story. So Wednesday last week, I went for dinner with my wife, Justine. Now, this would have been a source of anxiety for me in the past, and that's because some foods would leave me feeling really tired and sick for hours afterwards. And as a result, I actually followed quite a restrictive diet. Then I did Zoe and discovered that I'm prone to blood sugar spikes. From my Zoe digital coach, I learned that this doesn't mean I have to restrict what I eat. I just have to be smarter about my food choices. So back to last week at the restaurant. We were eating Italian, which before Zoe, would have left me feeling terrible. But my Zoe coach helped me make choices that consider my blood sugar. I started the meal with a delicious Italian salad and then enjoyed some pasta afterwards, drenched in olive oil, of course. And after dinner, I felt great, energized by my food and by the fact that now I don't have to limit the foods I eat and choose between a healthy and a happy life. Whether I'm eating out or cooking, my Zoe digital coach helps me make smarter choices every day. Honestly, it's transformed how I feel. And according to the scientists who continue to develop the digital coach, making these choices now could give me many more healthy years. Why not join more than 100,000 other people giving Zoe membership a shot and tell me what you think to take the first step towards the possibility of more energy, less hunger, and more healthy years? Take our quiz. To help identify changes to your food choices that you could make right now, Simply go to Zoe.com podcast, where as a podcast listener, you can also get 10% off.
Jenna Machoke
Is it just for dealing with colds and flu and nasty bacteria, or is there more to it with the immune system?
Dr. Jenner Machoke
I mean, part of the message that I love to share is that there's so much more to our immune system. And I think I've been very passionate about this subject for a long time, but I got kind of bored with just seeing it in the media being talked about as something that we think about when we get those familiar symptoms of a cold or flu, because it does so much more than that. But I think the infection is Something that people are familiar with, we can identify with the last time we caught a cold or a flu, and the feelings that we experienced when our body was dealing with that. So this is part of our immune system's weaponry. It's a very first line defense. So it's kind of like going out to battle, but not very specific. It's just like, oh, my God, there's a problem. You know, there's a viral infection in the lungs. Send in all the troops. They're not very specific, but they're just going to try and, like, deal with what's there. So, you know, you're unfortunate enough to inhale a whole dose of some, you know, respiratory virus, for example. Those viruses are going to infect the cells that line your airways, the cells that you use for breathing, for gas exchange. And by virtue of those viruses being in the CE cell's going to start to put out little red flags on its surface to say, something's up here. And that is a message to our immune system that something's wrong. So our immune cells are sitting there in the airways, making sure everything's nice and healthy. And as soon as they see one of our barrier cells of our airways put out that red flag, it's like, oh, right, there's a problem. They're going to go in and start killing our own cells that are infected. Which sounds quite dramatic, but that's to stop the virus from spreading.
Jenna Machoke
You said the cells say, hang on a minute, I'm getting infected. And our body immediately goes out and kills our own cells as a response.
Dr. Jenner Machoke
Yes, very.
Jenna Machoke
Sort of Game of Thrones it is.
Dr. Jenner Machoke
Yeah. Imagine, you know, zooming in to watch that unfold. But we have cells called natural killer cells. That's not a joke. That's the actual name of our immune cell. And that's because they are natural killers. And they have that ability to identify our own cells when they're damaged or transformed into something that's stressing them because they're trying to remove that damaged cell before the infection can spread. Because when a virus enters our cell, it turns it into a little viral replication factory so that it can burst out with hundreds more viruses. So you get this exponential infection. So we're trying to get on top of that before it can take off too far.
Jenna Machoke
That's amazing. So we saw we're killing our own body.
Dr. Jenner Machoke
Yes.
Jenna Machoke
Every time I have a cold.
Dr. Jenner Machoke
If you're traveling on the tube, you know, and you're breathing in all sorts of things, this is probably happening at a minute level. All the time before it even gets to the stage where you get symptoms. So there's a collateral damage. And this is an evolutionary trade off. You know, in order to survive in a world that is filled with microbes, there has to be that trade off and inflammation, really beneficial. You know, that's in the lungs, all these different, you know, chemical messengers from our immune cells to recruit in more, you know, backup troops to help deal with that before it becomes really, really a big problem for your body and you compromise the function of the airways. So, you know, you get pneumonia and you can't breathe properly. So we're trying to stop that happening, but we have to deal with the fact that there's some collateral damage. So your body is going to make some adjustments. And if you remember the last time you had a cold or flu, you might have felt a little bit poorly. Low energy, a fever, maybe some social withdrawal, maybe loss of appetite. And this is because your immune cells are putting out chemical messengers that are acting on your brain to change your behavior. And these are called sickness behaviors. Because we don't want you with your infection, going about your daily life, walking down the street, going into the office, speaking to people, because a, you're going to spread that infection, and b, you're consuming energy that your body could instead put into getting well again. And I think this herein lies the problem and that in the modern life world that we live in, how often do we just, you know, get up in the morning, feel lousy, but we'll go to the pharmacy, take all the things that suppress the symptoms, that is, suppress the immune response, so that we can go to the office and, you know, show up to work and, oh, I don't have a cold. And essentially treating those symptoms is stopping your immune system doing its job. And what we should be doing is listening to those sickness behaviors, having maybe one day on the sofa, getting lots of rest, because activating the immune response, activating that inflammation that's fighting off the virus is a really energetically costly thing for your body. So every 1 degree of fever that your body temperature rises, your basal metabolic rate is going up about 10%, you have a certain energy cost to running your body. So that's why, you know, we have to consume calories and then we obviously expend calories going about our daily life and all the different functions that are happening in our body. When you have inflammation and you're feeling all those sickness symptoms and you're fighting off an infection, your requirement for energy is going up because your body's Going to triage more of that energy into the immune system. There's sort of like a metabolic switch that says, okay, person's going to feel tired because we need that energy for the immune cells. So therefore, if you try and go and do some exercise, you're probably not going to have the same capacity as you would when you're healthy and your.
Jenna Machoke
Body is sending all of these signals. Because it basically says the best way that I can get better as fast as possible is to tell me to stop doing all those other activities so that I can sort of devote my body's resources to fighting this thing and maximize the chances that I can defeat it 100%.
Dr. Jenner Machoke
And also because it stops you spreading the infection. So there may be something like that that's dialed in through our evolution as well.
Jenna Machoke
I remember again, as a child, it's like, oh, well, you can't have the same thing that I have because, you know, you've got those cold symptoms. And I just feel really tired. So obviously it's a different bug, but it seems like it's not as simple as that.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
What is the link, I guess, between the symptoms that I have, you know, how much is that the virus? Is that my own immune system? And why is it, I guess, coming back to my mom and dad that she might be flat in bed for 24 hours and my dad, you know, must be exposed to it? I guess if they're in the same room and seems to sail through.
Dr. Jenner Machoke
Yeah, it's interesting. And there will always be a genetic component, so that's going to be one element of it. The way that your immune system can identify that infection and how quickly it can respond, that's definitely something that can be determined by our genetics. But then there'll be other things at play as well. And that can be everything from your health status, you know, how stressed you feel, how well you've slept or not. For example, after I had kids and I went back to work and my kids were in nursery, you know, they were bringing home so many colds and flus, as it happens when you have a lot of kids mixing together. And I remember they brought home a cold and everyone in the house got the same cold. And for a few days we were all feeling really lousy. But I was this new moment, coping with, like, this transition in my life, and I didn't slow down, I didn't stop. I was still going to work and yada, yada. And then I ended up with pneumonia because I was really stressed.
Jenna Machoke
That's terrible.
Dr. Jenner Machoke
Everyone else got Better from the cold. But I didn't.
Jenna Machoke
Is your explanation of that that you didn't rest or that your immune system was more compromised?
Dr. Jenner Machoke
I mean, I think it's a combination. And obviously this is an N of one experiment, which is science speak for.
Jenna Machoke
Saying it wasn't a full trial.
Dr. Jenner Machoke
Yeah, it was an observation case of myself.
Jenna Machoke
We are on a podcast, so you can. The floor is yours.
Dr. Jenner Machoke
I can declare that upfront. But, you know, if I sort of zoom out and remember that time in my life and I wasn't sleeping very well, I had twins, they were still small, still fragmented sleep. And I really found that transition to being back at work difficult. And I didn't rest because as a parent and, you know, juggling work, there isn't always that time. And I do believe that that will was important in what happened next because this lack of sleep, the stress, that's sort of an ongoing stress. And yeah, not resting, not listening to those sickness behaviors.
Jenna Machoke
And Jen, how would the lack of sleep and the stress affect your immune system? Cause again, I can hear my. I can definitely feel like hear. My grandparents would've been like, you know, that's all in your mind. Just like, yeah, you know, get on with it, get on with it. So that would all just be like being sorry for yourself.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
Is there actual real science that. That actually has an effect on your immune system?
Dr. Jenner Machoke
Yeah, there is real science. And this is where it starts to get complicated. Because, you know, we've spoken a little bit about genetics and a little bit about sort of other lifestyle factors like rest and things, but actually the immune system is the sensing system. So it's really in tune with what you're doing within your daily life. And it's taking in all that information and sort of calibrating and trying reach a point that's going to be useful for you at that moment. So it's really affected by stress chemistry. So we tend to think of stress as being something in our mind, but also we know that there's biochemical responses that happen within our body when we feel stressed. And our immune cells have receptors on their surface for those stress chemicals. So they're going to be responding to how we feel in the short term that actually helps the immune system. So if you imagine if you're about to walk out on a busy street and you didn't look properly and you're about to be hit by a car, you get a surge of adrenaline, you're going to run to safety, that stress chemistry is going to provide you with that instant energy and focus that you need to get out of the way. It's also going to prime your immune cells to respond in case of an injury where there could be an infection. So in the short term it's helping your immune response, but then over the long term you get things like cortisol, which is an important player in the stress response and that's going to have a suppressive effect on your immune system. So prolonged stress, we know, can make you more vulnerable to infections.
Jenna Machoke
And I don't want to get too miserable. And we will definitely come onto all the good things you can do to make things better. But I'd like to just sort of follow that thread to what scientists understand now is the impact of your immune system on your long term health. Because I've heard people talk more and more about how it's not just for sort of like this protecting you from a virus, but it could have an impact on your long term health. Is that right? And what.
Dr. Jenner Machoke
Yeah, I mean, I think it's really good to start by just thinking about our immune system in a different way. So we've spoken about infections and that's probably the way that most people are familiar with this thing that we call the immune system. But it does so many other jobs. You know, imagine if you were to, you know, break a bone and you don't have any infection there, but you've got damaged tissue. Again, just the virtue of tearing up some of your tissue is going to bring those immune cells in and they start to repair damage. So they're constantly doing this repair mode. They are our main cancer surveillance system. So this is something, again, people aren't aware of that your immune cells, you have specific immune cells patrolling your body all the time looking for or potentially cancerous cells and removing them before they become a problem for your body.
Jenna Machoke
Which is amazing.
Dr. Jenner Machoke
It's amazing. Yeah. And that's what has birthed the immunotherapies that we see coming out now which are being used to treat cancer. So it's helping our own immune system to identify a tumor and attack it, rather than just relying on the traditional slash burn poison. So surgery, radiotherapy, chemotherapy, where we're having to bring something in that attacks the tumor when we, we have an immune system that has evolved to be able to identify and attack tumors. So it's. Yeah, it's a really amazing bit of science that is going to change how we deal with cancer.
Jenna Machoke
And so does that mean that if I have like a poor immune system, maybe you're describing the stress and everything else it might mean that it's not functioning as well as it should. Does that increase my risk of cancer or other long term diseases?
Dr. Jenner Machoke
I think that's a hard question to study and a hard question to definitively answer. But we do have clues from the literature. People who suffer with certain conditions have higher risks of cancer. So there is a link there. But I think those real kind of longitudinal studies we haven't done yet, but I think that's something that, because we have now this much longer life course, we definitely need to be looking at.
Jenna Machoke
And then I'd love to ask you a bit about the microbiome, because my co founder, Professor Tim Spector, has sort of discussed with me and on this podcast that we now understand that an important part of what the immune system is doing is actually sort of managing all of these microbes in our gut, which in this case are not bad for us. They're not toxic, they're somehow an essential part of how we're meant to be.
Dr. Jenner Machoke
Yes.
Jenna Machoke
Is that right? And what's going on and how well do we understand this? Because I know that everything around the microbiome is quite new within science.
Dr. Jenner Machoke
Yeah, it's quite new, but so exciting. And it almost feels to me like it's been the missing piece in the puzzle of understanding our immune system. I mentioned earlier that a lot of our immune cells are congregated along the digestive tract, and that's where the bulk of the microbes that we carry are, are as well. So you think about the inner tube of our digestive tract having all these microbial communities living there, and then you have the gut barrier wall, and on the other side you have lots and lots of immune cells. And so this gut barrier wall is a really important interface between what's happening in the gut with these microbial communities and what's happening on the other side with our immune cells. And so there's a crosstalk that goes on all the time. And we now understand that when a baby is born and they start being colonized through all the microbes that they're receiving during the birth and then the first few years of life, that those microbial communities are able to directly influence and train and educate our immune system. And so having the right mix of microbes is going to be really important for that education piece to take place. And it happens in the gutter, but then it spreads throughout the body. So it's not just localized in the gut. And we've spoken a lot about inflammation and the sort of fighting arm of the immune system. And there's a lot of kind of military analogies that people will use. But I think one thing that's forgotten about is that you have to have the Peacekeepers as well. So you have to have the part of the immune system that comes in and turns things off when they're not supposed to be on, that, you know, clears up the damage and keeps the homeostasis within the body. And this is where this relationship with the microbiome was so important. So the microbiome are eating what we eat and they're breaking that down. And they're kind of metabolic waste products, I guess, are then going to be absorbed into our body. So there's one molecule, for example, called butyrate. Butyrate is produced by specific microbes when they eat specific fibers in our diet. And butyrate is important for various aspects of immune function. So it can directly act on immune cells to turn them into what we call T regulatory cells, or Tregs. And these are the key peacekeepers. These are the ones that are going to shut off unwanted immune responses. We know that they're really important in things like preventing or reducing allergies and autoimmune diseases. So these are conditions where our immune system has gone wrong and started chasing a target that actually isn't damaging at all.
Jenna Machoke
That's amazing. And one of the things we know, I think, is that we're eating diets that are very different from the diets we ever used to eat. You know, very little plants and fiber, lots of ultra processed food. And therefore what we're feeding these bacteria is very different. And most of us are not getting the amount of fiber that we would have done. So does this mean that, you know, in the past those bacteria would have been creating this butyrate that you're talking about and switching on this peacekeeping. And now for most people listening, this is probably not happening in the way that, you know, as it were, nature intended.
Dr. Jenner Machoke
Yes, it often feels like this system has been designed, that these microbes are our allies and they're producing things that it's so critical to the proper development of this part of our immune system. And when we're born, our immune system is actually quite underdeveloped. So a bit like the brain, you know, it has a lot of its development happening in those first few years of life, particularly in the first two to three years. And that's when we have a lot of changes going on with the established establishment of our microbiome. As the baby explores the new environment, whatever the feeding practices are and whatever the diet is. So you have very early on a trajectory being set in terms of that regulatory arm of the immune system. And when we look back through history, you can see that there is a strong correlation with the use of antibiotics from 1950s. Then we started having more convenience foods, ultra processed foods, dietary fiber intake drops. And this correlates to the explosion that we see in things like allergies, autoimmune diseases, and inflammatory diseases. And it's all kind of happened so very quickly. And now we have this problem where we're trying to figure out how to get back to where we need to be.
Jenna Machoke
Hi, I have a small favor to ask. We want this podcast to reach as many people as possible as we continue our mission to improve the health of millions. And watching this show grow is what motivates the whole team at Zoe to keep up the really hard work of creating new episodes each week. So right now, if you could share a link to the show with one friend who would benefit from today's information, it would mean a great deal to me.
Jonathan Wolf
Thank you.
Jenna Machoke
I think this idea that these tiny, tiny little bacteria might actually be training our immune system in the first couple of years is completely crazy. When I think about anything that I knew until 10 years ago. And really interesting to hear from you with your expertise, really, in the immune system. I'd love to move on now and pick up on the question that you talked about at the beginning that I think will have shocked a lot of people where you said, immune boosting is bad. Why isn't this a great thing?
Dr. Jenner Machoke
I mean, if you think about it, it's not a switch that we just want to flip on because the on is what we mentioned in the beginning. That's like tearing up, you know, your lungs with inflammation to fight off a virus. So it's really about this balance. And I think that we kind of think about it all the wrong way. We want to have, you know, something that will make us invincible to germs. And we live in this really germy world, you know, where they're everywhere. There's no way to be invincible, but we have to be robust and resilient germs. And that means that our immune system has to be able to respond well, but also do the peacekeeping as well, keep things under wraps when we don't need inflammation. So inflammation is such a damaging thing for our body. It should only be unleashed when we really need it. And we know that not getting enough fiber, not looking after those gut microbes, things like that, can actually increase what we call unwanted inflammation. And this is driving age related disease. So across the life course, rising levels of unwanted inflammation makes us more prone to age related disease. Things like type 2 diabetes, heart disease, certain cancers, frailty. And we want to be able to counterbalance that. So we don't necessarily always want this inflammatory response, this immune response to be on. It just doesn't make sense to me. In my head it's yeah, we want to have the balance, we want to have responses when we need it. But generally when we're not fighting an infection, we want the immune system to be off. We want calm and quiescent immune cells that are not spitting out inflammation. So the boosting part just doesn't make sense.
Jenna Machoke
Your body is jumping on everything when actually it could have just let it slide by and instead it's triggering all of these like very strong responses.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
When actually you're saying for many of us it would be better if our immune system was a bit more relaxed, not like more on.
Dr. Jenner Machoke
Exactly. Because I think there's so many things that trigger unnecessary inflammation. Stress, poor diet, lack of exercise, like pollution, like the list is endless. And actually we want to be turning that off as much as possible. So boosting, it's like, which bit are you boosting for how long, for how much? Like, because the immune system is this huge constellation of a million different types of cells and molecules. So to shrink it down to an on off switch, to me it's like it doesn't make sense. And I think it's just what I call immune washing. So people are taking advantage in terms of marketing terms, you know, because people are scared. You don't want to get sick. You want to get through winter without having to take time off work. And there might be something that contains a certain amount of vitamin C, which means they can use that immune boosting wording on their packaging. But it's not going to make you invincible to a.
Jenna Machoke
Could we talk directly about that? So if I take vitamin C, is it going to make my immune system better and mean that I am going to be sick less?
Dr. Jenner Machoke
I would love to say yes, but if you have a really good diet, I would definitely save your money. There is some evidence that if you perhaps you do a lot of running or a lot of sports and you're under a lot of stress and in those cases you might need a little bit more than you're getting from your diet and that might prevent incidents of illness. But we're talking really small and there's some evidence that when you start getting those symptoms you think, oh, I've got a bit of a tickle my throat or feel a bit, you know, fluy today, that your immune cells suddenly need so much more vitamin C. And if you start supplementing at the onset of symptoms, you might reduce the duration of the infection. And that's because vitamin C acts as an antioxidant and because inflammation is basically a big oxidative stress, so it's full of free radicals, it's damaging your own tissues. Your immune system is like, I need way more vitamin C right now because it's a great antioxidant. But, you know, I think the evidence is so small, maybe keep it in your cupboard, you know, and in winter, you know, it's something you could start taking if you fall sick.
Jenna Machoke
You're saying this, but I'm looking at you and you don't look like you believe that I should be taking vitamin.
Dr. Jenner Machoke
C. There is evidence there, but to me, I think the rest is probably a better way to, you know, that's where I'd put my money. Have an afternoon on the sofa, don't go into work, get some proper rest, you know, eat some really nourishing food, like delicious soup that's packed with, you know, lots of lovely vegetables and fiber and, you know, have an orange, things like that fruit and veg that's full of vitamin C and the citrus bioflavonoids and the flavonoids that are wrapped up with the vitamin C in food is going to actually help it work better and get into your body. So I'm kind of a food first person, but if you want to have a protocol based on the science, you could take, you know, a gram of vitamin C and spread it throughout the day with a supplement.
Jenna Machoke
And what about other supplements? There are various other supplements that people sell and say that, you know, you're going to take this thing and it's going to make your immune system better. What does the evidence say about that versus, like, being able to improve their overall diet and the things you were talking about before.
Dr. Jenner Machoke
I think there's two things we're thinking about here. One is that we often have a reactive approach to it, so we don't think about our immune system going through our daily life. Get into winter, first virus hits us and then we're like, oh, I've got such a terrible immune system. And then we take all the things that tell us they're going to make us better. I like to think about it in more of prevention in that looking after your immune system so it can look after you is a 365 day a year job. And that's, you know, what we should be doing every day, not just waiting till we get those symptoms and spending all the money because there's always that kind of bias that we've bought this supplement. It must be doing something. And do any of us ever really know if it's shortened the duration or made the symptoms better? Because you would probably get better anyway over the course of a few days. If it's, you know, a regular winter virus, you can find evidence for a lot of things. So elderberry, it's got antiviral compounds in it and there's been studies done looking at that also contains vitamin C. Echinacea is quite highly studied. The challenge there is that there's many different types of the plant and different bits of the plant. And so it's hard to get a consensus on which extract from which specific type is the one that's going to give you the best effect. And again, the science, we're not talking about huge meta analysis where we really have that convincing, robust data. It's going to be a mixture of small studies and things done on cell culture rather than in large populations of humans. You know, other things like garlic. We know that there's compounds in garlic that are really good for fighting off infections. But whether that's going to move the needle when you get those symptoms and whether you want to be chewing up raw garlic or you just want to be having, you know, something really nourishing and delicious, I'd love to switch on.
Jenna Machoke
Then to, okay, let's say you're thinking about this and you'd like to be more healthy, have more quality years and a better quality over the next year rather than just like, hey, I need to, you know, do this one thing and I know you discussed this in your, in your latest book about blueprint for strong immunity. And so I wanted to really touch into that and I think the three areas I'd love to cover to get like really practical advice for people listening. And I think you talk about nutrition, you talk about stress and you talk about sleep. And I just love to understand like what can you do where you feel there is really strong evidence that is really going to make a difference to this immune system that I think you've done a brilliant cell that like we really need to look after for the long run if we want to stay healthy.
Dr. Jenner Machoke
Yeah, I think have that long game in your mind. You know, we live on average to 80 years old, but our health span is 60 years old. And that's a delta of 20 years. And it's really emerging that the immune system is the key element to closing that delta.
Jenna Machoke
What you're saying is that you might only have 60 sort of quality years.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
And you're saying you're going to 20 years when you're feeling quite sick. And you're saying the immune system you think is the most important thing for trying to make that a shorter period of time.
Dr. Jenner Machoke
Yeah, exactly. And the things that are going to help that are also the things that are going to help you get through winter in terms of the sort of more short term feeling well and less downtime. And to me, the biggest piece of advice I can give to anyone in terms of diet is to follow a really anti inflammatory diet pattern and stop hyper focusing on superfoods. You know, if you eat five or six superfoods on repeat, that's not going to be as beneficial as a really diverse dietary pattern that's anti inflammatory. And I often reference the Mediterranean diet only because it's the one that's perhaps the most studied and has the largest volume of evidence behind it. But it's bringing in all those elements. So a variety of fruit and veg, using really good fats like olive oil, lean protein, oily fish and fiber. So, you know, we've spoken about the gut microbes, but making sure those gut bugs are fed and happy right from the outset and then across the life course, because that's not only going to be supporting your immune system, it's going to be minimizing that unwanted inflammation that's going to be sort of taking energy away from, you know, your ability to fight infections. It's going to be reducing the driving of those hallmarks of aging. It's really, really important, I think, that the overall pattern of your diet is considered rather than like, you know, we want to think of one or two superfoods, one or two supplements that we must take.
Jenna Machoke
And Jenna, can I ask you a question about that? So I follow, you know, the guidance I get from Zoe and my app every day and there'll be a lot of people listening who are members. And one of the things that has been most surprising to me and I think was quite surprising to, you know, my co founder, Tim Spector and a lot of the other scientists is the health outcomes we're focused on were a lot about improving long term health. But one of the things that's most surprising actually, when we look at the results from the random clinical trials, is how many people feel much better, very Rapidly after just a few weeks. And one of the avenues that the scientists are sort of investigating is this idea that it's sort of the microbiome affecting the immune system that could be affecting how you feel. I mean, is that what's going on? What do you think?
Dr. Jenner Machoke
I think there's a really strong hypothesis there. One area that I used to work in was the gut barrier permeability. So how leaky and permeable the gut barrier is. And that happens. There's a natural physiological response. Every time you eat that you experience a certain amount of leakiness. And that's normal and natural and it's part of the digestive process. But when you create any sort of leakiness in that barrier, you're going to get bits of whatever is on the inside of your gut. So microbes and bits of microbes and whatever else leaking into the body. And as soon as they're in the wrong place, they become a problem for the body. And when there's a problem for the body, the immune system's going to be alerted and it's going to turn on inflammation. So you get this postprandial inflammatory response, which in a healthy individual, when it's happening in a really normal physiological way is completely fine. But when we have a gut barrier that's not really robust because perhaps the gut microbes are a bit out of whack because of poor diet or medications, that barrier is already going to have more leakiness than it would normally and the inflammation is going to be increased. And that burden of inflammation, if you think about across the life course, is going to have an effect on all the things that drive aging. And I think this is what we have to think about when we're looking at that sort of long term health picture.
Jenna Machoke
And do we, because I started leading with this other question around, like how it makes you feel, like the mood and energy, is that back to the way this immune system can have this. You described about illness. Is that linked or is this something completely different?
Dr. Jenner Machoke
It's completely linked because inflammatory molecules that are being produced, as we spoke about before with the sickness behaviors are going into your brain and they're acting on your brain and they're making changes in how you feel. And we even know now that there's a subset of people with mental health conditions that respond to anti inflammatory interventions because it's like a form of sickness behaviors. So the response that we have when we have the flu that's meant to keep us lying on the sofa recovering is happening at a sort of low Grade level and making people feel depressed and have poor mental health.
Jenna Machoke
When I'm sick, I feel low. Like, it definitely affects my mood. I very rapidly am like, I'm going to be sick forever. I'm never going to feel good. I just feel bad about everything in the world. Like, that's a real thing that, like, my immune system is doing to me. It's not just. Again, if I just had a better stiff upper lip, like my parents, my grandparents, I would.
Dr. Jenner Machoke
I mean, you know, there might be some people who can really, like, dig deep and, you know, push through that, but it is a real physiological response driven by your immune system communicating with your brain to adapt your behaviors.
Jenna Machoke
And so this is an example of how it really can be true that the food you eat can genuinely change your mood.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
And why some of the terrible, ultra processed food we eat might be making us feel bad. But also how, if you could shift that diet, which I guess is what we're trying to do with Zoe membership and with this podcast, you can see the explanation for why we see this shift in mood quite fast.
Dr. Jenner Machoke
Exactly. Yeah.
Jenna Machoke
And presumably you're gonna say that, like, everything to do with this, both immune system and microbiome, it's understudied and there's a lot to understand.
Dr. Jenner Machoke
Yes, yes. Yeah. We've obviously simplified it down. And there's obviously the gut brain axis, where what the gut bugs are producing directly are going to be affecting nervous system, that route as well. And, like, there's going to be multiple pathways at play. But this link with unwanted inflammation being triggered is really having that impact on the brain. It's affecting our behavior. And it's also just that, collateral damage. You know, our body's having to do the repair on that all the time. So we want to minimize that as much as possible. We want to make sure that gut barrier is really robust. And the only way we can do that is by putting the right substrates in for those gut bugs to break down and produce things like butyrate, which is a direct fuel source for the gut barrier to fortify it and make sure it stays with its integrity. And if we're not putting the right fuel in, that mechanism can't happen. So you're going to compromise the gut barrier. And we now see links between this happening in the gut and autoimmune diseases. So things like rheumatoid arthritis, where the immune system's attacking the joint, we can see that. But by fixing the gut and improving the gut, we get an improvement in symptoms. Because what's Happening in the gut isn't obviously staying there. It's able to, you know, transmit around the body.
Jenna Machoke
Do you know someone who's always complaining about getting sick? Could they benefit from learning more about their immune system and what they can do to make it better?
Jonathan Wolf
If so, why not go ahead and.
Jenna Machoke
Share this episode with them right now. You'll empower them with the latest scientific advice and I'm sure they'll thank you. So you're saying that by changing what I eat and changing what's going on in my gut and my gut microbes, that actually then affects my immune system, that affects my arthritis in my knee.
Dr. Jenner Machoke
It can do. Yeah.
Jenna Machoke
It doesn't seem mad. I mean, you're used to it. But it's like I can eat something, just food. Right. We're not doing some magic. And that can actually reduce my arthritis symptoms.
Dr. Jenner Machoke
Yeah. By working at this gut barrier interface, by promoting immune regulation, these T regulatory cells, and by also stopping the microbes in the gut from being able to get into the body where they could travel around, cause inflammation in areas like the joints.
Jenna Machoke
That is amazing. There's a lot of anecdotal stories about that, actually, from members. And obviously Zoe is a wellness product, so it's not for treating any disease, but it's really interesting. That is one of the things that I've seen people just come up to me and talk about. And I have, prior to this conversation, been like, I don't know, it's amazing to hear this, the way that the immune system is sort of linking these very different parts of the body. I would like to talk about stress, which you mentioned already because you told this amazing story about how you ended up with pneumonia. What can you do? That could mean that you actually have an impact on your immune system by somehow reducing your stress. Is that possible?
Dr. Jenner Machoke
Yeah. This is probably the one I find most tricky from a very personal level because there's a lot of different stress reducing techniques, but often these are kind of of adding another layer to the lifeload. So I would say everybody needs to acknowledge the importance of stress as having this impact on your physical health. Don't think of it as something that's in your head and start to develop an awareness of stress and how it might be impacting your health. Often it's the last thing we come to. We'll, you know, audit other areas of our life. We'll audit our diet, our sleep, our existence, exercise. And sometimes actually wellness becomes a stress because people are trying to do things perfectly. I speak to a lot of People who see advice online and they can't quite apply it to their own life because perhaps it's been a bit misdirected. And that too becomes a stress. So I think it's really like remembering to put things in context. And I like to break it down and think of, you know, you have to have some in the moment stress tools. So if you have a really difficult meeting at work or a difficult phone call, you know, what can you do in the moment? And for me, it's things like getting outside, like widening the gaze. So we spend a lot of time hyper focused. And because our eyes are part of our brain, when we change the gaze, it's giving a signal to the brain that you're more relaxed when you have this broad view on the horizon rather than the laser focused looking at a screen.
Jenna Machoke
So you're literally saying, put the phone away, walk into the garden. And that actually can affect your stress?
Dr. Jenner Machoke
Yeah, it can affect your stress. I mean, we're talking like little minute things, but it's all going to add up. There's not just one lever that we're going to pull. So we've got in the moment, things altering your breathing. You know, so when you are inhaling, your diaphragm's moving down, your heart has a lot of space, the blood flow is going to go faster. This is going to give a signal to your brain that you have to slow the heart rate down and then you exhale. And so you have this thing called the respiratory sinus arrhythmia. So it's a constant interaction between the heart and these sort of mechanoreceptors, telling your brain when you need to speed up and slow down the heart rate.
Jenna Machoke
And Jenna, you're a very serious scientist. I just want to check. You are saying genuinely that changing your breathing could have an effect on your stress. That could genuinely have an impact on sort of your immune system. This is not just completely crazy woo woo, like that's actually real.
Dr. Jenner Machoke
It does sound woo woo. But when you think about the biomechanics of it, you know, when we inhale and exhale, we're sort of making more and less, less space inside our chest cavity. So the heart is going to pick up on that and that's going to give the heart more or less space. So the brain is going to tell the blood flow to speed up or slow down. And this is tapping into the two arms of the, what we call the autonomic nervous system. So that's your fight or flight response, which is kind of the stress arm and then the rest and digest arm, which is the more kind of relaxing, less stressed part of the nervous system. So the counterbalance distress and elongating the exhale. So just taking a normal inhale and then making sure that exhale is slowed down through the nose. This is going to really tap into that rest and digest parasympathetic part of the nervous system. So it's helping to bring a bit of calm back to the whole nervous system and help take the edge off the stress.
Jenna Machoke
There really are real clinical trials out there looking at reducing stress and those really do show an impact on the immune system. So this isn't just theoretical.
Dr. Jenner Machoke
This isn't just theoretical. Yeah. And we've spoken about the in the moment ones like just going out outside, changing the gaze, you know, Elon, getting the exhale. But I also think that we need some tools that are kind of a buffer for when it might happen. And you know, there's lots of studies on, you know, the long term meditators and people who practice different kinds of mindfulness. And these are the things that I think we need to not wait until we're stressed before we try. They're kind of the ones we should be trying to sprinkle through our weekend because they'll make us more robust if the stress comes.
Jenna Machoke
I'd like to finish with the last thing that actually you picked up on right at the beginning, which is around sleep. And you said that in your own case. I think again, when you're describing pneumonia, you're like, well, I don't know how much was the stress of small twins and how much was the lack of sleep.
Dr. Jenner Machoke
Yeah.
Jenna Machoke
What does sleep do to our immune system?
Dr. Jenner Machoke
Again, I love to look at things through the lens of evolution. And if you think during the day you go out of your house, you're interacting with people, you're exposed to germs, you're exposed to things that could damage you. So your immune system has a specific state during the daytime because that's when the risk is highest. And then when you go to sleep, you know you're sleeping and you would hope a safe, closed environment. So there's much less risk of injury, of infection, of things happening. So it kind of switches gears and performs kind of more housekeeping duties. So there's this real kind of circadian change in your immune system and it's again dialing into your brain. So it's a communication with your brain. Because when you're out and about and you see daylight, there's sort of Lots of genetic switches that will click and say, right, it's daytime, we need this kind of immune activity. And then again when it gets to darkness and we start to sleep, that again helps relay the signal to the immune system that we have to change and prepare for sleep. So that period when we're asleep is really important for this sort of housekeeping to happen. And earlier in our conversation, I mentioned the natural killer cells as being these kind of first line responders for viruses. And we know that they're very sensitive to sleep. So when we start to reduce the amount of sleep we get, we impair their ability to do their job. And so you can imagine as the sleep goes down, the risk of getting a cold or flu goes up. So the less sleep you're getting and the more you hop on the tube to work or go out and about and you're exposed to viruses, the less sleep you've got, the higher the risk that will actually end up a full blown infection.
Jenna Machoke
I love this. I need to sleep to let my natural born killers free to kill my own cells at night. This is like, it's slightly freaky. And final question just triggered by that, and it's probably crazy, you talked about how sleep is really important, that we need this sort of housekeep time for our immune system that, like, it knows it's certain times a day to do something different. And that's come up quite a few times on the podcast, but particularly talking about eating and the fact that there's a lot of evidence now that it's really important to have a long period of time when you're resting your gut, to allow your gut to go through all sorts of housekeeping. Has anyone studied at all whether there's any link to do with sort of time restricted eating or, you know, midnight snacking having an impact on your immune system? And these things are linked, or are they just two different examples of why it's important that we have a, you know, a day and a night?
Dr. Jenner Machoke
I don't know that it's been directly looked at, but the body loves routine. It sort of takes the whole weight off when there's an expectation of when things will happen. So there's lots of science about consistent bedtimes, as you said, consistent eating times and having that sort of period of rest between meals because it conserves energy, because then you know when to anticipate what to do when. And again, if we think about that gut barrier and the potential for inflammation when we're eating, if we have really erratic or sort of multiple meal times, then that post eating inflammation is going to be extended. And we want to really time box that into specific parts of the day so that our immune system can deal with that. And again, we haven't touched on it yet but, but there's a new field of immunology called immunometabolism and that's because our immune system is interlinked with our metabolism, because immune system is very energetically costly. So it needs to be talking to our metabolism to get the energy to fuel that. And you know, you touched on things like time restricted eating, eating you know, late at night and how that affects our metabolism. So you would imagine that there would be a natural downstream impact on the immune system if our metabolism is being affected by erratic eating times, eating late in the day or during the night. And we do see that the health of shift workers is affected by that. I don't know if anyone's ever looked at direct markers of their immune system, but I'm certainly going to look in the literature later.
Jenna Machoke
Well, I mean, as you know Zoe, we like to do really large scale scientific studies. So can I tempt you maybe to think about how we might do something about time restricted eating and impact on the immune system?
Dr. Jenner Machoke
You don't know what a geek I am. I'm like, like my brain is already starting.
Jenna Machoke
I'll follow up with Dr. Sarah very afterwards and she'll probably already, as soon as she listens be like, that's fascinating. But I am really intrigued by the way in which you're describing how much of the immune system is managing these bacteria. And we know, I think from, you know, a lot of actually scientists working with us that you know, what's going on inside the microbiome is actually changing sort of during the, the period when you're not eating. And so there's clearly something important that's going on there. But you're saying that the puzzle pieces haven't all been put together.
Dr. Jenner Machoke
Yeah, but I think there's a picture I can see that is worthwhile exploring.
Jenna Machoke
It's very exciting. I think for anyone listening, what you see here again is just how much the science around all these areas is still new. And so when you talk to someone who's at the cutting edge and we're very lucky to do that, you're also often saying these are the things we don't understand yet.
Dr. Jenner Machoke
Exactly.
Jenna Machoke
Which I always think is the marker of a scientist. You should try. Can I try and do a quick summary of at least some of the things we covered? A lot I Mean, my starting point is you said this one thing, we live in a germy world, so we can't be invincible. We're going to get these things. And actually you don't want your immune system to be super boosted, which in the long run that could be really harmful. And the reality is actually our immune system is on too much. And this is what's leading to things like more risk of diabetes, but could always can impact your risk of cancer. So actually we want a sort of calm immune system. And the immune system is having like a much bigger impact than we realize. So you know, for example, you know, if I am sick, it is true that that immune system is sending, you know, chemicals to my brain that are actually gonna make me feel bad, like lower my mood, make me tired. And that we should. You're sort of suggesting don't ignore it all, take all the pills to stop it going away. Like this is actually sort of signaling to you how to, to respond. The other thing I think that's amazing you talked about is that the bulk of our immune system is actually where our microbes are and that we now know that the microbiome is really important for sort of fine tuning. You described the immune system, that that's somehow something critical that's happening when we're in our first few years of our life, that somehow these microbes are even training us, which is really weird. And that basically a bunch of stuff has been going wrong over the last 50 or 60 years, whether it's antibiot, change in food, ultra processed food, all the rest of it. So we see this really big rise in allergies and autoimmune. But it also means that today you said that our microbiome should be producing a whole set of chemicals that are sort of helping the peacekeeping part of our immune system. And I think you mentioned this thing. Butyrate.
Dr. Jenner Machoke
Butyrate, yeah. As one example.
Jenna Machoke
As an example. But basically it's like our microbiome should be like arming the peacekeepers. And that's not happening because we're not eating the right food and we don't all have the right good bugs. And therefore somehow our immune system is one of the, in which our immune system is out of balance. Like we got all the guys out there with the guns, but we've got none of the sort of calming side of this. That is why the food you eat is gonna be much more important than popping a particular superfood or a vitamin C. But then I think you talked about two other really interesting things. That I think a lot of us felt maybe weren't real. And you're saying this is real. As a scientist who studies this, which is stress has a direct impact on your immune system. This isn't made up. It's not just in your head. You can measure it in a lab. It's physical. It's also really hard to reduce, is what you're saying, which made me feel better. But there is real clinical evidence that things that sound crazy, like breathing exercises, could actually reduce your stress. Putting the phone outside and just going outside. And that if you can reduce your stress, it will actually improve the function of your immune system. That's important. And that sleep, which again, I remember when I was young, it's like sleep is for wimps, actually. Sleep is really important. Cut back your sleep, you're going to worsen your immune system. Because I've got these natural born killers in every part of my body, but they only come out when I go to sleep. This combination of things can really have an impact on this immune system. And that immune system is really affecting every part of my health.
Dr. Jenner Machoke
Exactly. It really is the kind of the arbiter of our health across the life course. And it's a very complicated system. I think any immunologist would put their hands up and admit that we really haven't got it all figured out yet. But there's so many inputs that are going into it, and we do have some control over those inputs. So it's trying to think about all the little things that we can do and thinking of that compounding over time rather than just like, oh, I've got sick, what can I take? Just like the little things we do every day, I think add up.
Jenna Machoke
Amazing. I really enjoyed that. I hope we can get you to come back in the future because I think there's lots of areas here we haven't touched and we will follow up on that in your research.
Dr. Jenner Machoke
Oh, thank you. It's been a pleasure.
Jenna Machoke
It's been wonderful. Thank you, Jim. Jenna. I really enjoyed having Jenna on the podcast today. I learned a lot of new things and I hope that you did as well. My biggest takeaway is that there's never a quick fix for solving your health. So, you know, taking that vitamin C when you're sick isn't what's going to matter. It's about actually having gradual and sustainable changes over time that just improves the state of your immune system, the state of your health permanently. And if you listen to the show regularly, then you probably already believe that and you probably already believe that you can transform your health with food. But now there is only so much you can learn from general advice on a weekly podcast. If you want to feel much better.
Jonathan Wolf
And be on track for more healthy years, you need something more. And that's why each day more than.
Jenna Machoke
100,000 people rely on Zoe Membership, our personalized nutrition program, to make smarter food choices to feel better in weeks and.
Jonathan Wolf
Be on track for more healthy years.
Jenna Machoke
So how does Zoe Membership work? First, your at home tests allow you to understand your body's responses to food and the good and bad microbes in your gut. Then Zoe's app uses your test results to create your personalized program helping you build life changing nutrition habits step by step. Your program includes recipes, meal plans, food scanning and simple scores out of 100.
Jonathan Wolf
For any meals meal.
Jenna Machoke
And regularly retesting your gut health lets you track your progress. I rely on Zoe's advice every day and truly it has transformed how I feel.
Jonathan Wolf
So will you give Zoe a try? The first step is easy. Take our free quiz to find out.
Jenna Machoke
What Zoe Membership could do for you.
Jonathan Wolf
Simply go to Zoe.com where as a.
Jenna Machoke
Podcast listener, you can get 10% off using the code podcast. As always, I'm your host Jonathan Wolf. Zoe Science and Nutrition is produced by Seb Masters, Julie Pinero, Sam Durham and Richard Willen. The Zoe Science and Nutrition podcast is not medical advice and if you have any medical concerns, please consult your doctor. See you next time.
ZOE Science & Nutrition: Immunity Tips for Healthy Ageing with Dr. Jenna Machoke
Episode 4 | Release Date: October 31, 2024
Introduction
In this enlightening episode of ZOE Science & Nutrition, host Jonathan Wolf engages in a deep dive into the complexities of the immune system with Dr. Jenna Machoke, a Senior Lecturer in Immunology at the University of Sussex and author of The Science of Staying Well and Your Blueprint for Strong Immunity. Together, they unravel the myths surrounding immune boosting, explore the intricate workings of the immune system, and provide actionable insights for maintaining a healthy immune system to promote healthy ageing.
1. Debunking Common Immune System Myths
Timestamp: [00:37]
Dr. Jenna Machoke begins by addressing the surge in immune-boosting products following increased public interest. She questions the very essence of what it means to "boost" the immune system and whether such an endeavor is even feasible.
Notable Quotes:
These statements challenge the prevalent notion that enhancing the immune system's activity is universally beneficial. Instead, Dr. Machoke emphasizes the importance of balance within the immune system.
2. Understanding the Immune System's Complexity
Timestamp: [04:48]
When asked to define the immune system, Dr. Machoke elaborates on its dispersed nature, explaining that unlike the digestive system, which can be pinpointed anatomically, the immune system is ubiquitously present throughout the body. It comprises immune cells, molecules, and organs working in harmony to protect the body.
Notable Quotes:
This section lays the foundation for understanding the multifaceted roles the immune system plays beyond merely fighting off infections.
3. Genetics, Stress, and Environmental Exposure
Timestamp: [03:28]
Exploring the factors influencing immune system performance, Dr. Machoke discusses the roles of genetics, stress, and environmental exposure. She highlights how genetic inheritance from both parents contributes to immune responses and how lifestyle factors like stress and exposure to germs can impact immune health.
Notable Quotes:
This segment underscores the interplay between inherent genetic factors and external lifestyle influences in shaping immune function.
4. The Immune System's Role in Long-Term Health
Timestamp: [09:51]
Dr. Machoke broadens the discussion to the immune system's critical impact on long-term health, beyond its immediate role in combating infections. She explains how the immune system is involved in tissue repair, cancer surveillance, and maintaining overall bodily homeostasis.
Notable Quotes:
Highlighting the immune system's extensive responsibilities, this section emphasizes its influence on conditions like cancer and autoimmune diseases, marking it as pivotal for healthy ageing.
5. The Microbiome-Immune System Connection
Timestamp: [23:22]
A significant portion of the conversation delves into the relationship between the microbiome and the immune system. Dr. Machoke explains how gut microbes play a vital role in training and regulating the immune system, particularly during the early years of life.
Notable Quotes:
She introduces the concept of butyrate, a metabolic byproduct produced by certain gut bacteria, which is essential for maintaining immune balance by promoting regulatory T cells that prevent excessive inflammation.
6. Diet's Influence on the Microbiome and Immunity
Timestamp: [26:44]
The discussion transitions to dietary habits, highlighting how modern diets—rich in ultra-processed foods and low in fiber—disrupt the microbiome's ability to produce beneficial compounds like butyrate. Dr. Machoke correlates these dietary shifts with the rise in allergies, autoimmune diseases, and chronic inflammation over recent decades.
Notable Quotes:
Emphasizing the Mediterranean diet, Dr. Machoke advocates for a diverse, anti-inflammatory dietary pattern that supports both gut health and immune function.
7. Stress and Its Physiological Impact on Immunity
Timestamp: [18:46]
Addressing the pervasive influence of stress, Dr. Machoke elucidates the biochemical pathways through which chronic stress suppresses immune function. She shares personal anecdotes, including her own experience with pneumonia, to illustrate how prolonged stress and lack of rest can compromise the immune system's effectiveness.
Notable Quotes:
This segment underscores the tangible physiological effects of stress on immune resilience, debunking myths that dismiss stress as merely a mental burden.
8. Practical Strategies for Immune Support
Timestamp: [36:33]
Dr. Machoke offers actionable advice for listeners aiming to bolster their immune systems through sustainable lifestyle changes. She emphasizes the importance of an anti-inflammatory diet, stress management techniques, and adequate sleep.
Notable Quotes:
She advocates for holistic, long-term approaches rather than quick fixes like supplements, promoting a balanced lifestyle that supports immune health continuously.
9. The Critical Role of Sleep in Immune Function
Timestamp: [49:57]
The conversation highlights the essential role of sleep in immune regulation. Dr. Machoke explains how sleep facilitates immune system housekeeping, enhances natural killer cell activity, and reduces susceptibility to infections.
Notable Quotes:
Emphasizing the evolutionary aspects, she details how sleep aligns with the immune system's need to repair and maintain bodily functions without the constant threat of external pathogens.
10. Integrating Diet, Stress Management, and Sleep for Optimal Immunity
Timestamp: [54:15]
Bringing together the various elements discussed, Dr. Machoke advocates for a cohesive strategy that integrates a balanced diet, effective stress management, and sufficient sleep to foster a resilient and well-regulated immune system.
Notable Quotes:
She emphasizes that these lifestyle factors collectively contribute to minimizing unwanted inflammation and supporting the immune system's multifaceted roles in maintaining health and preventing disease.
Conclusion
The episode concludes with Dr. Machoke reiterating the importance of gradual, sustainable lifestyle changes over quick-fix solutions for immune health. She underscores the interconnectedness of diet, stress, and sleep in shaping immune function and encourages listeners to adopt a holistic approach to support their immune systems for healthy ageing.
Final Takeaways:
Dr. Jenna Machoke’s insights offer a comprehensive understanding of the immune system and provide listeners with evidence-based strategies to enhance their health and longevity.
References:
Disclaimer: The content discussed in this summary is based on the podcast transcript and should not replace professional medical advice. Always consult with a healthcare provider for medical concerns.