Recap: What is inflammation and how can I control it | Prof. Philip Calder

Summary

ZOE Science & Nutrition Podcast Summary

Episode: Recap: What is Inflammation and How Can I Control It | Prof. Philip Calder
Host: Jonathan Wolf
Guest: Professor Philip Calder
Release Date: January 21, 2025

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Introduction to Inflammation

The episode begins with Host Jonathan Wolf highlighting the frequent mention of inflammation in discussions about various health conditions such as Alzheimer's, cancer, and heart disease. Recognizing the complexity and the critical role inflammation plays in health, Jonathan introduces Professor Philip Calder, an expert in the field, to demystify the concept of inflammation and provide actionable dietary advice to manage it effectively.

Notable Quote:

"It's designed to help us. It's designed to be part of our protective mechanism." – Prof. Philip Calder [00:51]

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Understanding Inflammation vs. Immunity

Professor Calder elaborates on the distinction between inflammation and immunity. He explains that while the immune system encompasses a broad and sophisticated defense mechanism against pathogens like bacteria and viruses, inflammation is merely a component of this system.

• Immunity: A comprehensive defense system involving various cells and processes to protect against harmful environmental agents.
• Inflammation: The initial response under the umbrella of immunity, acting as the body's immediate reaction to injuries or infections.

Key Points:

• Inflammation is not inherently negative; it's essential for healing and defense.
• Problems arise when inflammation is unregulated or occurs inappropriately, leading to chronic health issues.

Notable Quote:

"Inflammation is the first little part of the immune response... we shouldn't mix up inflammation and immunity." – Prof. Philip Calder [00:51]

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Types and Risks of Inflammation

The discussion shifts to the prevalence of elevated inflammation levels in modern Western lifestyles and the associated health risks.

• High-Grade Inflammation:
  Linked to autoimmune diseases such as arthritis, multiple sclerosis, and type 1 diabetes. Elevated inflammatory markers like C-reactive protein (CRP) are prevalent in these conditions.

• Low-Grade Inflammation:
  A more recent focus over the past two decades, this persistent but lower-level inflammation is associated with common diseases including heart disease, obesity, type 2 diabetes, and dementia.

Measurement:

• C-Reactive Protein (CRP): The most common blood marker used to assess inflammation levels.

Notable Quotes:

"Arthritis, multiple sclerosis, type 1 diabetes. These are diseases that clearly involve inflammation gone wrong." – Prof. Philip Calder [02:30]

"The inflammation in arthritis and so on has been known for decades... low grade inflammation has really only been known for about 20 years now." – Prof. Philip Calder [03:41]

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Dietary Strategies to Control Inflammation

Professor Calder emphasizes the importance of long-term dietary changes over quick fixes to manage inflammation. He outlines several key dietary components that can help mitigate and resolve inflammation:

• Omega-3 Fatty Acids (EPA and DHA):
  Found primarily in fish and seafood, these fats play a significant role in reducing inflammation. They are also available as fish oil supplements.

• Extra Virgin Olive Oil:
  Rich in anti-inflammatory compounds and recommended as part of a healthier dietary shift.

• Vitamins and Polyphenols:
  Vitamins C and E, along with polyphenols found in fruits, vegetables, and nuts, contribute to anti-inflammatory effects.

• Fiber:
  Supports a healthy gut microbiome, which in turn can influence inflammation levels.

Notable Quotes:

"I would prefer to think of a long term dietary shift away from things that are considered to be less healthy... more Omega 3, more fiber would be part of that." – Prof. Philip Calder [04:40]

"Lots of things in the diet that we can use to mitigate ongoing inflammation... things that give fruits, vegetables, berries and so on their colors, they're also anti inflammatory." – Prof. Philip Calder [06:00]

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Deep Dive into Omega-3 Fatty Acids

A significant portion of the discussion is dedicated to Omega-3 fatty acids, particularly EPA and DHA, highlighting their sources, benefits, and the impact of dietary changes on their availability.

• Sources of Omega-3s:
  Primarily obtained from oily fish such as salmon, as well as fish oil supplements. Vegetarian and vegan alternatives are also available through supplements.

• Benefits:
  Anti-inflammatory properties that help mitigate both meal-induced and chronic inflammation. EPA and DHA are vital for resolving inflammation, essentially signaling the body to "turn off" the inflammatory response.

• Research Evidence:
  Professor Calder cites robust human studies, including epidemiological data and randomized controlled trials, demonstrating that higher intake of EPA and DHA is associated with reduced risks of heart disease, dementia, certain cancers, and metabolic disorders.

Notable Quotes:

"Omega 3 is a general term for a group of fatty acids. EPA and DHA are a type of omega 3... they seem to have quite pronounced anti inflammatory roles." – Prof. Philip Calder [05:21]

"We have animal studies, we have all sorts of studies, but I'm mainly interested in human evidence... people who eat more fish or people who eat more EPA and DHA... have a much better long term health outcome." – Prof. Philip Calder [09:15]

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Impact of Factory Farming on Omega-3 Availability

The conversation addresses concerns regarding the quality of Omega-3s in farmed salmon compared to wild-caught varieties.

• Farmed vs. Wild Salmon:
  Most supermarket salmon is farmed, relying heavily on fish oil (75% of global fish oil) to ensure their health and growth. However, due to sustainability and cost issues, the industry has reduced the reliance on fish oil, substituting it with vegetable oils. This shift has resulted in farmed salmon containing lower levels of EPA and DHA than their wild counterparts from previous decades.

• Health Implications:
  While farmed salmon still provides Omega-3s, the reduced levels mean they offer less anti-inflammatory benefit compared to wild salmon or farmed salmon from the past.

Notable Quotes:

"Farmed salmon still is a good source of EPA and DHA. It just doesn't have as much as it used to." – Prof. Philip Calder [14:16]

"The industry has found out a way to reduce its reliance on EPA and DHA and therefore reduce the cost of farming salmon." – Prof. Philip Calder [13:43]

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Conclusion and Recommendations

Professor Calder concludes by affirming the strong evidence supporting the inclusion of oily fish in the diet to combat inflammation. He advocates for a balanced, long-term dietary approach rich in Omega-3s, extra virgin olive oil, vitamins, and polyphenols to effectively manage and resolve both high-grade and low-grade inflammation.

Final Recommendation: Incorporate fatty fish like salmon into your diet regularly to ensure adequate intake of EPA and DHA, thereby leveraging their anti-inflammatory benefits for improved overall health.

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This episode of ZOE Science & Nutrition offers a comprehensive exploration of inflammation, distinguishing it from general immunity, elucidating its role in various diseases, and providing evidence-based dietary strategies to manage it. Professor Philip Calder's insights underscore the significance of Omega-3 fatty acids and advocate for mindful dietary choices to foster long-term health.

Transcript

[Host]

Hello and welcome to Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're discussing inflammation. I hear this word a lot from guests on the Zoe podcast. It's always coming up when I ask about health conditions like Alzheimer's, cancer, or heart disease. It's clearly very important. However, many of us still don't feel fully understand what inflammation really is. Professor Philip Calder is here to break down inflammation and share tips on what we should eat to keep it in check.

[Interviewer]

Can you explain in simple terms what exactly is inflammation, how it's different from immunity, and why? You're saying it's not necessarily always a bad thing?

[Professor Philip Calder]

Yeah.

[Expert]

So immunity, our immune system, is the way we defend ourselves against harmful things in our environment, particularly things like bacteria and viruses. Now, immunity is very complicated, very complex, it's very sophisticated, and it involves many different things happening in the body, many different cell types and events occurring. Inflammation is the first little part of the immune response. So immunity is sort of like an umbrella of very complicated but joined up, and inflammation is just part of what's under that umbrella. So we shouldn't mix up inflammation and immunity. Now, because inflammation is part of immunity, it's actually designed to help us. It's designed to be part of our protective mechanism. So inflammation is really the first thing that happens when we get exposed to something harmful. And that could be an infection, it could be an insect bite, it could be, you know, a paper cut. So the things that people experience when they get a paper cut or even a more serious cut, you know, the pain, the redness, the swelling, that's inflammation. So that's designed to help us. So it's something that happens in a helpful context. But it turns out if it's not regulated properly or if it's happening in the wrong place at the wrong time, that's when it becomes harmful to us.

[Interviewer]

I understand most of us living in a sort of Western lifestyle today probably have higher levels of inflammation than we should. What is this? What's the risks as a result?

[Expert]

Arthritis, multiple sclerosis, type 1 diabetes. These are diseases that clearly involve inflammation gone wrong. And if you measure chemicals in the blood of people that are indicators of inflammation in those patients, the levels of those chemicals are very high in the blood.

[Interviewer]

So this is. You can measure the inflammation of somebody with a blood test that gives you a real answer.

[Expert]

There are chemical readouts in the blood that are elevated, that are higher in someone with an inflammation in the joints.

[Host]

For example, like arthritis Is there one.

[Interviewer]

Particular thing you look at or is it a set of things?

[Professor Philip Calder]

So the most common marker is a.

[Expert]

Protein called C reactive protein or crp. That's a very good indicator that someone is inflamed. But there are others as well. So in these disease scenarios we would consider that to be high grade inflammation. So the levels are very high. But we also have other conditions where there is elevated inflammation. So too much inflammation, but not at.

[Interviewer]

This, really not this sky high level.

[Expert]

So we call that low grade inflammation.

[Interviewer]

Okay.

[Expert]

Of course the inflammation in arthritis and so on has been known for decades now. But this phenomenon of low grade inflammation has really only been known for about 20 years, I guess now. And it turns out low grade inflammation is part of many common diseases that people wouldn't think of as inflammatory diseases. So things like heart disease, for example, heart disease, heart disease, obesity, type 2 diabetes, even dementia. So these common diseases are linked with this low grade but persistent inflammation.

[Professor Philip Calder]

So that's part of the risk profile.

[Expert]

If you like, for these conditions.

[Interviewer]

And is it like one magic pill, like if I take, you know, we often talk about extra virgin olive oil as being very good for you. Does that mean if I'm taking a shot of extra virgin olive oil three times a day, like that will solve my inflammation, like a pill from the doctor? Is it as simple as that?

[Professor Philip Calder]

I wouldn't prefer to think of it like that. I mean I would prefer to think of a long term dietary shift away from things that are considered to be less healthy. And I mentioned in general what they might be in the context of this postpartum inflammation and a move towards things which we think are more healthy. And you know, olive oil, particularly extra virgin would be part of that. More micronutrients, I mentioned vitamin C, that would be part of that. More Omega 3 trees would be part of that. More fiber would be part of that.

[Interviewer]

People know what extra virgin olive oil is, they know what nuts are. That was really clear. And I know your own research, you've done a lot of your own research around Omega 3.

[Expert]

Yes.

[Interviewer]

Could you tell us what Omega 3 is? Cause I, you know, I don't see that on the shelf. Like I see olive oil.

[Professor Philip Calder]

Yeah, so you do see it on the shelf. It's just you have to go to a different shelf because you'll find salmon on a shelf in the supermarket. So when I talk about omega 3s, I'm mainly talking about the fish sourced omega 3s, EPA and DHA. So omega 3 is a general term for a group of fatty acids. EPA and DHA are a type of omega 3. They are, as I mentioned, sort of uniquely linked with fish and other seafood. They seem to have quite pronounced anti inflammatory roles. Both if you put them in a meal, they will help to mitigate this meal driven inflammation. If you have this inflammation already going, be it high grade, but that's a disease like arthritis or this low grade persistent inflammation associated with aging, are there dietary components that can dampen that inflammation? More importantly, are there dietary components that can help you resolve the inflammation? There's lots of things in the diet that are anti inflammatory. They include omega 3s, which I'll come back to shortly, but also some of the vitamins, vitamin C, vitamin E or anti inflammatory, lots of the polyphenols from plants. So the things that give fruits, vegetables, berries and so on their colors, they're also anti inflammatory. Things in nuts are anti inflammatory. Gut microbiome is also a driver of inflammation, but also could be anti inflammatory if you get it right. So there's lots of things in the diet that we can use to mitigate ongoing inflammation. I think these omega 3s, EPA and DHA that come from fish and they're also in fish oil supplements by the way. So people can go to a different shelf and get some EPA and dha. And we might want to consider that in the context of people who choose a vegetarian or vegan approach. We've been working on EPA and DHA for 30 years now. They are anti inflammatory.

[Expert]

Okay, that's clear.

[Professor Philip Calder]

Lots of experiments show that. But the really interesting thing has been discovered in the last 15 years or so. This process of resolution of inflammation, the turning off, you know, flicking the light switch off if you like, involves chemicals again. So everything in the body is involving chemicals sending signals. Researchers in Boston discovered that some of the key chemicals in resolution of inflammation are actually made from EPA and DHA in the body. So EPA and DHA are the substrates, the starting point for making chemicals that turn off inflammation. People have studied omega 3s, EPA and DHA and arthritis actually since the 1980s. And it's well described that high levels of EPA and DHA as a supplement can help people with arthritis in terms of painful joints, tender joints, stuff like that morning stiffness. And everyone always said this is an anti inflammatory effect. But actually if you think these are people who've already got high grade inflammation, I think what's happening is EPA and DHA are acting to resolve the inflammation. So actually to take that high grade and bring it down a bit. And that's why people with arthritis benefit from, from EPA and dha.

[Interviewer]

Imagine someone's listening to this and saying, I want to understand how to make some shifts to my diet in order to reduce this inflammation. Maybe starting with the sort of omega 3 and oily fish. I know that's your big focus. How strong is the evidence, in your opinion that yes, if you're willing to eat fish, you should be adding oily fish to your diet. Will it make a difference?

[Professor Philip Calder]

For me, the evidence is very strong, yes. We have animal studies, we have all sorts of studies, but I'm mainly interested in human evidence because, you know, doing something in a laboratory and some mice is one thing, but we need human evidence. And in human research in nutrition, we really, in general, we have two types of research. One is where you look at diets, foods, nutrients, levels of nutrients in people's blood, and you track what happens to those people over time. So, you know, we call that epidemiology. The epidemiology of omega 3s is extremely strong. In other words, people who eat more fish or people who eat more EPA and DHA, or people who have more EPA and DHA in their blood have a much better long term health outcome. Less heart disease, less dementia, some cancers, less cancer, less metabolic disease, all that stuff. So the epidemiology is very strong. The other type of study we have is treating nutrition a bit like a pharmaceutical. So a randomized controlled trial. Typically these are smaller in size and shorter, so they might involve tens or hundreds of people. But I think if you step back and look at the really important things like heart disease, for example, even from randomized controlled trials, there's pretty good evidence that higher intake of EPA and DHA reduces risk of heart disease and mortality from heart disease. And certainly they impact beneficially lots of the biomarkers that tell you about risk. So I think for me the evidence is quite strong and I personally would recommend that people should incorporate these sort of fatty fish in their diet if they can.

[Interviewer]

I've been part of quite a few conversations with Tim and Sarah talking about the fact that a lot of oily fish today would come from salmon, which is now factory farmed and very different from the sort of fish that we would have got in the past. And I know that Tim is quite skeptical about this because he feels that there might be a lot of other reasons to feel that this is not really so good. How do you think about sort of the sort of factory farm salmon that you would actually probably get if you went to the grocery store?

[Professor Philip Calder]

Yeah, I think, I think that's a great question. And salmon, I think, is a really good example because salmon farming is a massive industry. And probably most of the salmon that's available in the supermarkets is farmed salmon. People will be familiar with fish oil, which is, you know, they'll think of an omega 3 supplement that they can get from a chemist shop or, you know, a supermarket or online. And, you know, fish oil contains EPA and DHA, these really important omega 3s. Okay? Now, in the wild, salmon eat other fish and they get EPA and DHA from their diet by eating other fish. So if you farm salmon, traditionally you had to give salmon, EPA and DHA in their food, otherwise they didn't grow well and they didn't stay healthy. And the biggest user of fish oil is the salmon farming industry that uses something like 75% of global fish oil is actually used in salmon farming. Now, first of all, that is a limited resource. And you could argue, if it's so important, why don't we give it to people instead of to fish? But the fish need it if we're gonna farm them. So it's a limited resource. And it's also expensive, okay? It's a commodity. It's much more expensive than vegetable oil.

[Interviewer]

For example, and that's because it actually comes from other fish.

[Professor Philip Calder]

Is that where the fish oil comes from? So you've got to invest in the production of fish oil. The research behind fish farming has been trying to find out what happens if we give salmon less fish oil and replace it with vegetable oil. So it's well described that salmon can still grow and do well if you give them less fish oil than they used to be given and you replace that with vegetable oil. The consequence of that is farmed salmon have less EPA and DHA in their flesh than wild caught salmon. A farmed salmon now will have less EPA in DHA than a farmed salmon did 20 years ago.

[Interviewer]

Okay. So that farmers are figuring out ways to make this more profitable.

[Professor Philip Calder]

The industry has found out a way to reduce its reliance on EPA and DHA and therefore reduce the cost of farming salmon. I guess. So. One interpretation would be the overall health benefit is less from a farmed salmon now than it used to be, let's say 10, 15, 20 years ago, and less than a wild salmon. Okay? However, farmed salmon still is a good source of EPA and dha. It just doesn't have as much as it used to.

[Host]

That's it for this week's recap. If you're hearing this, you're already on your way to making smarter food choices with world leading science. Speaking of making smarter food choices, Zoe membership helps you to do just that with scientific solutions that let you listen to your gut. Listening to your gut starts with an at home test kit that helps you understand your body's responses to food and the good and bad microbes in your gut. Then Zoe's app helps you build life changing nutrition habits step by step. Become a Zoe member today and give your gut the love it deserves. The first step is easy. Go to Zoe.com and use the code podcast to get 10% off. As a Zoe member, you'll get a comprehensive at home test kit and personalized nutrition program. So go to Zoe.com and get 10% off with code Podcast.