THE MICROBIOME SUMMIT : The New Path to Health
The Role of Microbes in Aging
Dr. Brett Finlay, PhD
Dr. Brett Finlay has shown us how important our microbes are to infancy and early childhood – but microbes are also important in our senior years. As we age, our microbes not only decrease in number, but also in overall diversity. In this interview, Dr. Finlay will discuss how to keep microbes healthy as we age. Dr. Finlay will highlight why we should care about our microbes, and the role they have on inflammaging – the chronic, low-grade inflammation that is epidemic in the later years of life. Inflammaging can make it hard to lose weight and even contribute to heart disease and brain diseases like dementia and Alzheimer’s.
- Tracey:
- Hi Brett. Thank you for joining me here today.
- Brett:
- Hi. Thanks.
- Tracey:
- You are working on a new book that’s going to focus on microbes in the aging population. So, are microbes just as important to us in the aging process as they are to us when we are in our infancy?
- Brett:
- The way I see it in terms of microbes, the two bookends of life, early in life and late in life, that’s when there’s the most changes to your microbes. So, the reason I’m thinking about doing this book is, you know, every parent says, “Well, I have my kids now what about me?” You know, none of us are getting any younger. That got me interested in this and I’ve been looking a lot into it and what I’m finding is actually it’s spectacular. I must admit I’m very surprised at some of the things I’m seeing. And I think the moral of the story …. so then we thought well, we’ll just write it on healthy aging, you know, 65-plus or 55-plus, but then we realized even 20, 25, 30 years of age microbes play a big role in a whole bunch of things about your health and disease. So, the book will probably, it will basically be adulthood, really. But the biggest effects are seen later in life. You know, 65-plus, because your microbiota just goes off a cliff in terms of its composition. It becomes very different and there’s a lot of thought that that even actually impacts on the whole aging process.
- Tracey:
- Interesting. So, do we see – I’m not really that familiar with this research so – do we see a decline in the numbers and also the diversity?
- Brett:
- We see a very big decrease in diversity. It becomes very homogeneous and when you just would look at the composition of these you’d immediately say, oh that’s not a good microbiota to have based on what we know is a healthy microbiota. The diversity decreases. Part of it might be, you know, if you go into a care home, for example, the diet you have is very homogeneous and within a year of going into these elder care homes everyone’s microbes become pretty much the same and these are not very healthy in terms of microbes. It could be partially the fact that your immune system quiets down and immunosenescence as you get older. I think the one big thing that I’ve learned about the whole aging process is this. As you get old you have a sort of chronic low-grade inflammation. They call this “inflammaging”. Anything that precipitates that actually seems to really precipitate a lot of the diseases as you age. But just for a fun experiment took the top 10 reasons why we die in our society, right? When you look at that, there’s only one that’s infectious. That’s number eight; it’s influenza and flu, lung diseases really, due to the microbes. But then I really re-calibrated that and looked where everything …. what has the micro component? And nine of those 10 diseases I can say have a micro component. The only one I couldn’t blame microbes for are accidents. You can’t say that microbes made me do it. But all these other, cardiovascular disease, you know, and heart attacks and strokes, there’s amazing stuff come out there, lung diseases, COPD, et cetera. There’s big stuff there and especially brain diseases, dementia, Alzheimer’s, there’s some very, very strong microbe correlates coming up there. They all seem to play, pretty much all these things that we all die of …. So, that’s been really the motivation and as I dig into these I’ve learned all sorts of things. Even fun stuff, you know, cosmetics, you know, skin wrinkles. It’s funny. You ask a guy, they care about baldness. You ask a woman, it’s skin wrinkles. There’s some neat studies coming out that if you take the microbes off the skin of a 20-year old woman and put them on a 50-year old woman it actually makes her skin less wrinkly and helps the skin health, kind of thing. So, there’s talk about microbial banking, you know, stash your microbes when you …. I can take a skin swab of a person’s face and tell you within 10 years how old they are, if they’re bald or not, just by the microbial composition that changes as you age and it seems to …. So, it’s behind where the kids data was but boy it’s coming and coming strong, yeah.
- Tracey:
- Very fascinating. I understand the whole concept of inflammation but can you explain just how the microbes may promote inflammation?
- Brett:
- Yeah, so, I mean, inflammation is your body’s reaction to foreign invaders, especially microbes, and it’s generally designed to help fight them off. But let’s take dementia, for example. Dementia and Alzheimer’s is one of the top 10 reasons people die and we all worry about this. There’s some fascinating studies out that, if you brush your teeth three times a day you can decrease your dementia rate by 20 to 40 percent. Just by brushing your teeth. Another twins study showed that twins with very poor oral health, they had much higher rates of dementia also. What does that mean? Well, it turns out what we realize is that if you have inflamed gums, periodontitis, what happens is that the microbes seep into the body and they have these molecules that alert the immune system, things such as called LPS, and this basically elevates the whole inflammatory level of your body by all these things seeping through your unhealthy gums to the rest of the body. We already knew it had a big effect on heart attacks and heart disease but we now realize this also affects how the brain seems to be involved in triggering these Alzheimer’s/dementia type diseases.
- Tracey:
- That is absolutely fascinating. I think, probably, the number one question that I get from my aging population in my practice is, “I don’t want to get dementia, I don’t want to get Alzheimer’s, I don’t want to get Parkinson’s disease, what can I do?”
- Brett:
- Diet can play a major part. There’s this thing called the mind diet, which is a modified, basically a modified Mediterranean diet. That can, if you restrict – that’ll cause a 50 percent decrease in your rates of getting this thing, getting those types of diseases. Usually don’t stick to it perfectly, you can still drop it by 35 percent by just eating that way. What does that mean? Well, diets are basically microbes and they influence microbes. So, it’s the standard stuff. Diet, of course, exercise plays a role in it. There are some very interesting studies coming out now on how the microbes are shifted by exercising. There’s a neat book called The Blue Zones. There are seven areas in the world where people live forever. So, when you look, what are these …. Costa Rica, Okanagan, Sacramento, sorry Loma Linda, California. What do they have in common? Well, they generally have three things in common. One, they’ve got a social network. They’ve got either friends, or your religion, you get together a lot, or you’ve got extended family. So, you have social contact. Number two, they’re fairly active. They will toddle down to the town square and play bridge with their friends. You don’t have to be a marathon runner, but you’ve got to be active. And a third thing which comes through again and again is diet. So, they don’t eat much bread or meat, they might have a pig roast at New Years but it’s not a major part of their diet. It’s interesting, in California where they are Seventh Day Adventists so they’re vegetarian by religion which obviously helps them. They eat a lot of nuts and things. They eat a lot of plant fibres, nuts, legumes, all the stuff your mother said was healthy and you didn’t want to eat but maybe you should. Now you should eat it not just for nutrient but for the microbes they are actually feeding. So, I think when someone asks you that what I say now is probably the best is diet and exercise. Then we look at what we feed elderly people, especially in these care homes, I mean, it’s brutal in terms of well-balanced – I mean they’re getting white bread and bologna, that kind of thing, and it’s really screwing their microbes.
- Tracey:
- Have there been studies that have looked at the change in the diversity and the numbers of microbes when somebody does adopt this type of diet, even when they’re 65?
- Brett:
- Yes, to some …. I mean, when you change your diet within a day that’s reflected in your microbes. So, the second you do something you will see that right away. These are unfortunately sort of long-term experiments so they have to follow people over years that are following it. But I think there’s a lot of data to indicate that’s really the, you know, the diet is shifting the microbes having beneficial effects. While I’m on diet, I might talk about obesity which is another area that I think there is really exciting stuff coming out. One is that there’s this group in Israel. They’ve made a bunch of people wear glucose monitors and they’re looking for peaks in glucose levels which is a precursor to obesity and diabetes. So, they made these people wear these things. They tracked everything they ate, they tracked what caused glucose spikes, they tracked what microbes they had and put this big bioinformatics pipeline together and based on that they can actually now analyze anyone’s feces and they can say, well, if you eat these foods like pizza and ice cream you will get a glucose spike, but these foods won’t. And so based on that they can design a personalized diet and each of us has completely different gut microbes so they’re different between different people. Based on that, they can actually analyze people’s microbes and say that you should have this personalized diet and if you stick to it, the experiments show this thing just blows away the standard diets. So, it makes sense but I think this is a whole new way in terms of …. Another thing I’ve learned that just came out recently is something called yo-yo dieting. So, okay it’s Christmas, we gain a few pounds, New Years resolution ‘let’s lose that’ and we go on a diet, we do the stuff and next year we’re up by a pound or two more but we do the same thing every year, so you sort of go like this, so it’s called yo-yo dieting. What’s been shown only in mice so far, but a really neat study, is microbial memory. If you go on a diet and get off, the last thing you should do is try and go on a diet again. What happens is you won’t lose weight. You can actually take the feces from mice that have been put on a diet and stopped, put it in normal mice, put them on a diet, they won’t lose weight. It’s this microbial memory. It you translate it to humans it takes about five years to remember to then forget that, okay now I can go on a diet and lose weight. So, I think it’s really exciting because in society we’re gaining weight as a society every year. So, maybe these microbes are playing a role in this even though we do go on these diets all the time. Maybe it’s why we’re not losing weight.
- Tracey:
- What are some, three key messages that you would want a 65-year old to hear?
- Brett:
- Right. Well, I think brain health is the big issue. We all worry, the last thing you want to do is lose your mind. And so brain health, of course, is …. we were talking about brushing your teeth, oral health and then diet. I think you need to stay active as much as you reasonably can. You know, if you don’t use it you’re going to lose it and just sitting in front the TV the entire day, that’s not good because that also affects your microbes. And then I think social contact. There are some interesting studies showing you can actually tell who your bridge partners are in an elder care home by the microbial composition because you’re swapping microbes when you swap the cards and things. And so, and also having, you know, extended families. The way we look after seniors right now is actually, I think, wrong. You lock them up in their own little room where they don’t see anyone. I think, you know, the whole social contact which is sharing the microbes, right? So, I think those are probably the biggest messages.
- Tracey:
- Right. By the title of your book, Let Them Eat Dirt, I mean it just conjures up the image of sending people out into nature and hugging trees or gardening or ….
- Brett:
- But how did we evolve, right? If you go back 100 years, 1,000 years, 10,000 years, what were we doing? We were crawling around the ground picking up nuts, you know. Kids were playing in the dirt. The way we live now, the question I hate the most is, a woman’s living on the 22nd floor of a condominium in an urban setting, she had to have a C-section, the kid had to be bottle fed. This woman says, “Well, how do I get my kids normal microbes?” How do you? I don’t have a good answer to that. You know, say, get a dog, go outside, go to the playground, those will help a bit. But the biggest thing I worry about is with each generation we get cleaner and cleaner. We are getting rid of the microbes that even, you know, one generation ago they were there. So, you extrapolate that by 10 generations, what are we going to be? We’ve evolved with these all our evolution. Ironically, I tend to think of the microbe as an endangered species in a sense because we’re getting rid of them and we can’t go back. We’re taking a piece of our evolution out of us as a species and so it’s a very bizarre way of thinking. People sort of roll their eyes when they start thinking about this but I think the data is pointing us in that direction.
- Tracey:
- In terms of an aging population, I mean, when you explain, you know, the scenario of the seniors in their isolated rooms, living in their care facilities, would you want to see policies change so there has to be some sort of shift where there has to be mandatory outdoor time, mandatory gardening, you know?
- Brett:
- Just like in school. Yeah, well, partly. I think diet is a big part. I think we really need to think. It’s not just calories, it’s, you know, are you eating white sugar, white flour? That’s absorbed by us in the small intestine and it doesn’t even reach the microbes. You’re full but you’re starving your microbes. So, you know, whole plant fibre type thing, health diet is important. I think it’s got to start long before you end up in that home. I think just normal lifestyle plays a major role in it and, you know, people in their 20s, 30s and 40s need to be really thinking about their microbes because that will set them up for longer term life. Yeah, I think that, the main thing is I think there’s a lot of promise here. Microbes are easy to change. We can change them much easier than …. you can’t do a change in a human gene right now but we can change your microbes just in diet and probiotic type of thing. So, I think medically there’s a lot of hope for intervention fairly quickly as opposed to trying to develop a drug for a particular human enzyme, for example. So, I think it’ll be embraced fairly quickly in the medical area and we can actually maybe dent this whole aging issue.
- Tracey:
- Thank you.
- Brett:
- My pleasure.
