The Food Medic - S7 E8: Immune boosting facts and fallacies with Jenna Macciochi

Episode Date: February 23, 2022

Never before has the immune system had so much air time - but what actually is the immune system? Can it be boosted? What kind of things influence it? Does vitamin C really fight off a cold and there truth in the old wives tale - feed a cold, starve a fever? I’m Dr Hazel Wallace, host of the food medic podcast and on this episode we are answering all those questions with immunologist and author Dr Jenna Macciochi. Jenna has a PhD in allergy immunology from Imperial College London and has previously worked in academia, pharmaceutical industry and clinical trials. Jenna currently holds a Lecturer position at the University of Sussex progressing research into understanding the science of lifestyle related disease. This episode covers:- What actually is the immune system? - Factors which influence our immunity- Can you boost your immune system with food?- Should you feed a cold and starve a fever?- What steps to take to recover from a cold - Exercise and immunity - The importance of sleep and your immune system. If you loved this episode make sure to give it a review, rating (hopefully 5 stars) and share it with your friends and family. @thefoodmedic/www.thefoodmedic.co.uk Hosted on Acast. See acast.com/privacy for more information. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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Can it be boosted? What kind of things influence it? Does vitamin C really fight off a cold? And is there truth in the old wives tale, feed a cold, starve a fever? I'm Dr. Hazel Wallace, host of the Food Medic podcast. And on this episode, we're answering all those questions with immunologist and author Dr Jenna Machoke. Jenna has a PhD in allergy immunology from Imperial College London and has previously worked in academia, the pharmaceutical industry and clinical trials. Jenna currently holds a lecturer position at the University of Sussex progressing research into understanding the science of lifestyle-related disease. I think first of all I would just love by asking you

a little bit more about you, who you are, what you do and what you're passionate about. Yes, so my name is Jenna Machocki, I'm an immunologist. I'm currently at the University of Sussex, where I teach immunology to a broad range of different degree programs, pharmacy, medicine, biomedical science, anyone who needs to know about the immune system. And I've been in the field nearly 20 years. I love research. I'm really passionate about immunology and the immune system. And I feel like it's one of those fields where the more I learn, the more I feel there is to learn. And I'm so passionate about all the different inputs that are shaping our immune system. Because as I came to realise a few years ago,

there's so much written about the immune system, but not all of it is incredibly accurate. So I like to try and communicate what I know in a way that's really accessible to people and kind of inspire them to to see the immune system as fascinating as I do. Yeah amazing and I completely agree with you I think you know there's always chat about the immune system and immunity and I mean the last couple of, it's never been such a hot topic. But I don't think everyone fully understands what we mean when we talk about the immune system. I know. I think that's a great place to start because we do tend to kind of speak about it as if it's a binary on off switch. You know, you want to switch it on. You want it boosted. You want to turn it off again.

But it's actually, as the name suggests, a system. So I like to see it as a kind of all-embracing, all-encompassing wellness system. It's as indispensable for your health as your heart or your lungs. And it plays an important role, not just in infection protection, which is mostly what we think about when we talk about our immune system, but it's really important to all areas of your health including mental health. It's sort of everywhere and nowhere so it includes everything from your white blood cells which are found not only in the blood but they tend to be congregated at the body barriers so that would be the skin, the lining of your lungs, the lining of your digestive tract, anywhere that's exposed to the environment and where there could be some trauma or infection and you might need the immune

cells to dive in and do their work. But we also include the barriers themselves to your body, so the skin, the airways, the gut and the microbes that live atop those areas so the microbiota those good microbes we include that in the definition of what the immune system is there's very few places that you'll find that don't have some kind of presence from the immune system yeah absolutely and I love that kind of what you mentioned in the beginning that it's not this on off switch the way we talk about it and we often do and obviously there are things that influence our immune system and how it functions and I think that will be a really good place to start kind of what things influence it that we can control and maybe some things that we can control.

Yes I think that's important especially in the context of the last two years with COVID, because immunity has been firmly at the top of everyone's mind. And it's something that's been talked about endlessly in the media. And, you know, I guess we like to simplify things down into tangible things that we can do to have agency over our health. But part of what shapes our immune system is things that we can't control and this includes things like your genetics and also things like early life events how you were born where you were born in the world your geographical location things like gender and race all of these play a role in a way that we can't control your age although that's somewhat modifiable. And then there's all the things that we can control. So these come down to the sort of key tenets of lifestyle, which would

be, you know, what we're feeding ourselves, how we're moving our bodies, how we're managing our stress, things that we can do to nurture our microbiota, the good microbes that live on us and in us, and how we're sort of resting and sleeping, moving our body. Things like body composition are really important because both muscle and fat are active immune organs. So having the right balance of these is really important to the overall functioning of your immune system. Yeah, I think a lot of people know that food influences their immune system, or I know that I get a lot of people know that food influences their immune system, or I know that I get a lot of questions, you know, what can I eat to boost my immunity,

or what should I do to prevent a cold, and X, Y, and Z, but not everyone is fully aware that all these kind of different things that we do in our day-to-day lives, like how much we sleep, the stress that we're under, all of that as well impacts our immune system. Yeah, I often think of it as, you know, you could have this really perfect diet, super nutritious and covering all your bases, but you know, you're very stressed because of certain life events, and you're not sleeping very well, and you're over-exercising or under-recover under recovering and so you're missing out on all those other key inputs that the perfect diet isn't going to make up for that magically you know think about having your health as a cake and you want to have that strong base from all those different sort of

lifestyle inputs and then all the fancy stuff and the supplements is more like the icing on the top it's not very healthy to think about your health as a cake but it's an analogy that works for me no I do like it so I mean when when people do talk about boosting their immune system it's often around food and supplements vitamin c is the big one that comes to mind or garlic turmeric there are so many what's your take on this yeah so I mean I guess in my field we always say there's no scientific way that you can boost your immune system except perhaps with a vaccine booster so that would be the correct way to use that term but we can provide it with some of these essential inputs that it needs and some of those are of course nutritional so while there's a few different nutrients and

foods that seem to get elevated as being really important for your immune system I think that in the data we see time and time again that it's the overall pattern of your diet that's important so it doesn't matter if you're eating five superfoods regularly but what are you eating across the entire week? And are you covering all your nutritional needs? Garlic, I think there's pretty good body of evidence that it does play a role in how our immune system works to fight infection. Turmeric, again, there's like growing evidence on its role as an anti-inflammatory agent. Things like vitamin C is a nutrient that our immune system

needs in extra amounts when we're fighting an infection but none of these are going to be some sort of magic wand on their own if you don't have it in the right context of everything else so are you getting enough protein are you eating enough fiber these kind of things so when you're advising someone in terms of even though it does not exist I'm using like in quotation marks like the best diet for your immune system are you just basically encouraging people to eat a healthy balanced Mediterranean style type diet yeah I think what comes out on top is the anti-inflammatory diet patterns and of which the Mediterranean diet kind of has the lion's share of the research it's not the only anti-inflammatory diet patterns and of which the Mediterranean diet kind of has the lion's share

of the research. It's not the only anti-inflammatory diet pattern, but it's one that's very well studied. And the kind of key things that stand out on that is that if you're eating this way, you're going to have all of your micronutrients covered. So these are the nutrients we need in small amounts, the vitamins and minerals. And I know we often think about vitamin C and zinc has been really important for the immune system, and they do play important roles. But if you're deficient in any of those micronutrients, that could impair the function of your immune system. So it's having those micronutrients covered, but also the macronutrients. So protein is a really important

nutrient for the immune system. And actually, perhaps not so much in the UK, but worldwide, protein deficiency is one of the biggest causes of immune deficiency. So it's a really important nutrient for our immune system, because it's the building block of all those antibodies and cells that our immune system is using when it's fighting an infection. Fats are also important. So the omega-3 fats, which come from oily fish, or you can get them from supplements. These actually make up the membranes of our immune cells and help them to function properly and move around the body properly. They are also part of switching off inflammation and resolving inflammation at the end of an infection. And then your carbs are important too, not just for energy, and they can also be a source of

micronutrients, but they can be the source of fiber, which is going to feed the microbes in your gut. And we have a huge amount of immune tissue located in the digestive tract, and it's up close and personal with those microbes and they have a really close relationship and they're those microbes are kind of the key educators and trainers of our immune system so we want to be fertilizing them and cultivating that ecosystem inside us and then these nutrients from the fiber are being digested by the microbes and produce our own kind of personal pharmacy of of compounds that are absorbed into the blood, they can have broad ranging effects on our immune system. So we know that eating dietary

fibre and having a healthy microbiome can influence the lung immune system and how well we respond to respiratory infections. So it's not just staying in the gut. And then finally, things like the Mediterranean diet is full of different colored fruits and vegetables so all that fresh produce and the pigments in these plants called phytonutrients of which there's many many thousands are kind of working together as a symphony to have broad ranging effects on the immune system they work at the genetic level helping switch on and off genes And I like to call them longevity nutrients, because they're kind of not things that we have a recommended daily amount that we need. But

the more we get, the better it seems to be for our health span. So it's really building that bank account for the future. And also calories matter, matter you know when you get a fever you get a about 10% rise in your basal metabolic rate for every one degree that your temperature rises when you're fighting an infection so you need to have enough calories to be able to fuel those immune responses when you need them. Yeah which is slightly the opposite of that old wives tale which is you know feed a cold starve a fever do you think that we should be eating almost more or just being more conscious of the foods that we're eating when we are you know struggling with the fever do you know what there's some interesting science actually about the old wives tale feed a cold starve a fever

and there seems to be a kernel of truth but it depends on what type of infection you have. There were some amazing studies they were done in mice so we don't know that this would be the case in humans but they found that when the mice were suffering from viral infection they did better when they were fed but when they were suffering from a bacterial sepsis infection they did better when they were starved and they thought that perhaps being starved restricted the immune system from overshooting so it sort of restrained the inflammation because when the immune system overshoots as it can do it can actually cause our bodies sort of collateral damage. They've tried to look at how that might translate in

humans with people who are suffering from sepsis which is a life-threatening condition but so far I think the data's been quite mixed and I would say to anyone you know you probably don't know what kind of infection you have unless you're getting tested properly so probably just eat if you're hungry and you know when you're not well your appetite may change but as long as it's in the short term it should be fine. Yeah and so kind of thinking more broadly about then fasting and our immune system and people just kind of doing it more from a kind of a health protocol as opposed to getting through a sickness is there any evidence to say that fasting may support the immune system or the opposite even? There seems to be I think we

just don't know what the key duration and type of fasting would look like it certainly seems to cause a sort of transient stress on the cells of the immune system and it helps us sort of clear out the old ones and it acts on the bone marrow which is where our new immune cells are produced so it's kind of helping encourage fresh new cells this also happens when we exercise as well so it's not just from fasting I think you just have to be careful and it might not be appropriate for everyone it is a stress so if you're already feeling pretty stressed it's just sort of adding to that life load and might be more of a negative effect and you have to take care that you're not actually under eating some of the key nutrients that I mentioned they're important for the immune system I'm really excited to see what comes of that field though because I know there's a real active area

of interest in it and in the research community yeah absolutely I think like you said there's so many different protocols that it's very very difficult to kind of find out what's the right one for you and you know there's other health implications to keep in mind as well yeah um so say you know you've been looking after your health you've been taking all the steps that you mentioned but you come down with a cold What steps do you recommend people take to recover? Do you know what, I feel quite passionate about this, even before COVID, because I feel like we have this culture of presenteeism, which means like we go to work, even though we're not well, just because we're like, look, I'm still even though yeah like it's not one stir and you're

coughing and I kind of thought maybe that would change with COVID because people were suddenly more vigilant and wouldn't go out if they had any symptoms of any kind of respiratory infection but I've also been on online calls with colleagues who have COVID but they're like oh I'm on Zoom so it doesn't matter. But I think the first thing to do is, you know, as I mentioned before, you have this rise in your basal metabolic rate when your body is fighting an infection. So your body's triaging energy into the immune system to allow it to do its job. So you don't want to be doing all your normal activities in your normal life. You probably just want to rest and I think there's perhaps a case for you know having one day or two days of rest rather than just

continuing as normal maybe taking some over-the-counter pharmacy medicines to to help with your symptoms and it probably takes you longer to get well so I'd say the first thing is to rest and let your body have that time to recover. Do you offer like the same advice for someone with Covid? Oh for sure I think it like any infection that you know let your body have that time to recover and I guess if you're in quarantine then you've got the force upon you that you have to stay home and you can't go about your normal day to day life. The other thing to remember is that getting sick a few times a year is normal. Like people going into winter and I get a lot of people asking me, like, how can I avoid being sick? How can I get to the other side of winter without getting sick?

And I'm like, well, you probably have to retreat from the world and not see another human because germs spread where people meet so even if you're very healthy and you take very good care of yourself there's a high chance that you'll get a couple of minor infections a year and that's totally normal because we live in this germy world so I always try and encourage people not to sort of have this fear of germs you You know, in the UK, we're very lucky that we don't have some of the more sinister infectious diseases that are present in other parts of the world, or we can vaccinate for here in the UK. So get your rest, don't panic. And then think about your health cake. So get the basics in place. You know, I think there's a lot of utility in things like nourishing soups, where you can pack in lots of yummy vegetables, but if you're not feeling well, it might be a bit

soothing to eat if you don't really feel like making a proper meal. And also the heat and the steam can help ease any congestion. There is some scientific evidence that chicken soup does have certain compounds in it that can help certain immune cells work better um so if that's something that you enjoy then that could be something to have and then staying hydrated because um if you have changes to the mucus in the nose or the respiratory tract obviously if you're dehydrated that can affect the consistency and affect the mucus's ability to do its job and get rid of any microbes that are infecting you amazing and so no kind of special supplements focus on the low-hanging fruit first yeah well I think so I mean you know I get it that you know when you take some supplements or you buy

something you're investing in your health in that way it gives you know when you take some supplements or you buy something you're investing in your health in that way it gives you a sense of agency over your health and you you kind of maybe get a bit of a part placebo effect because you think well I've spent money on this it's got to do me some good and it is true that our immune cells use a lot more zinc and vitamin c when they're fighting an infection and And there's some evidence that supplementing when you get the onset of symptoms may shorten the duration of the illness, but it's quite minor. So I think if you want to keep it in the cupboard, it's not something you need to take every day and it won't prevent you from getting ill. There's another supplement called lactoferrin,

which is something that's actually found in breast milk it's a compound we produce ourselves our body barriers but they've found a way to sort of isolate it and put it into a supplement and there's quite a lot of emerging evidence that taking that when you get sick can reduce the duration of symptoms too so there are things that you can do but I think if you're generally looking after yourself well and you have that good baseline then you should bounce back in a timely manner anyway so I feel like it's the little things you're doing all the time that pay off on the odd occasion that you might fall sick with something yeah and like you said it's normal to kind of get a cold every now and then especially throughout the year but just thinking about that now you know recently we've we've come into cold and flu season here in the UK anyway and there was like all these media reports of like super colds and super flus

and people having the worst colds ever where do you think that's coming from is that just because we've you know had this like 18 months of really locking down and being really good with our hand hygiene and wearing masks that we're exposing ourselves to colds and flus again or do you think that we've forgotten what it's like yeah it's a really good question and I think it's quite hard to unpick exactly what is going on. I do think that it sort of depends what you did in those sort of almost two years since COVID arrived during the lockdowns. For some people, the lockdowns were very stressful and it may have really changed their diet and lifestyle habits.

So they may have become more unfit and, you know, had sort of poorer dietary habits. And they might be from an immune standpoint in a poorer situation. But for others, it might have done the opposite. Maybe they were getting outdoors a lot more, doing a lot more physical activity, eating better. So that's sort of one way to look at it. Some people might just be in a worse situation immunologically because of what effect lockdown had on them there's also you know since the germs could not spread when we were all shut away there's a different pattern happening of the distribution of germs and we are seeing a different shift in how that's happening so respiratory respiratory succinctal virus was peaking a lot quicker in

the autumn and in a shorter duration of time than what the normal pattern would be. So then you see this real spike of young kids who can get quite sick from it in early life, just a kind of different pattern than normal. It was more condensed. And that also could be that mothers, if they've been exposed recently, will provide some immunity to their children so if the lockdown they hadn't been exposed then the child wouldn't have any of that maternal immunity to that particular virus and then you know a lot of the viruses that cause the common cold I mean there's hundreds of them it's unlikely that you'll see the same one twice but they do have a lot of the viruses that cause the common cold, I mean, there's hundreds of them, it's unlikely that you'll see the same one twice, but they do have a lot of cross immunity. So if you get one cold

and cold virus, it might give you a little bit of cross protection to another cold virus. But if you haven't seen any cold viruses for two years, then your immunity to these cold viruses drops off quite quickly anyway. So you kind of need that continual exposure so that they're mild so it could be a combination of any one of these factors that could have led to what we've seen in the last few months as we've gone into winter. Yeah multiple things going on at once I guess and so you know you mentioned that stress and the stress of lockdown is has been a big factor and I think like a lot of us when we do kind of feel a bit run down let's just say we often link

it back to stress and the other things that are going on in our lives how strong is that link between stress and us falling sick yeah I think it's really emerging as one of the single most potent contributors to ill health at the moment. I'm sure anecdotally people would be able to relate that stress can really worsen or increase the risk of just about any health condition that you can think of, both physical and mental. And whether that stress is something that's emotional or something else, it's always a physiological response in our body. And that's mediated by else it's always a physiological response in our body and that's mediated by things like the sympathetic nervous system which is there to it's there to protect

you in the short term so you know if you're about to get hit by a bus you need that stress chemistry to be released to motivate you to safety or if you have a big race coming up or a sporting event that little bit of stress is actually very good to get you going. But I guess it can tip over into being quite detrimental quite easily. And the stress chemistry has broad physical effects on your body to be able to provide you with that energy to get to safety or to achieve what it is you want to do. So it changes things like your blood sugar, your heart rate, your breathing, and even your immune function. And it sort of triages your energy away from your immune system. So it's saying, well, I'm not going to fight off this cold.

I'm going to use that energy to plow into the stress response because that's more immediate, which is fine if it is a short term stress, but most of us in today's world experience more intermittent and prolonged stresses. And we know that this can be a huge detriment to immune function. There was a really interesting study that came out very recently that showed that chronic stress is actually accelerating our biological age. And we know that the aging of our body is not always the same as our chronological age. And we know that the ageing of our body is not always the same as our chronological age. And ageing is one of the biggest risk factors for poor health or infections like COVID. So this seemed to be linked to immune function when the stress chemistry is there,

it's deregulating the immune system when we have raised inflammatory markers and so we know that there's this real connection and it's having these real broad effects but I think it's just quite hard to to rein it in it's really hard I mean I am a personal stress head I have to work really hard to manage my stress and I think that that comes from getting support, having psychological resilience, and, you know, learning different ways to regulate your emotions. It's challenging. And I think it's something we need to be teaching our kids probably in school, particularly after the last couple of years. Yeah, I completely agree with you. It can be difficult to offer kind of practical solutions when a lot of the stress that's occurs in our

life can be external and sometimes out of our control but I think it's useful to be aware of that and encouraging to take you know practical steps to reduce your stress and manage your stress where possible and I think you kind of alluded to it it is very personal and so like what's relaxing and de-stressful for one person can be stressful for another um I always think that there's a lot of tools and resources online but you need to kind of furnish your own toolbox of what are the things that work for you so maybe meditation is just going to stress you out more but maybe there's other things that you can do that are going to work and I I think, you know, there's certain things we can do in the moment with how we breathe or going for a walk that can really help when you have that immediate, you know, somebody sends you this email that stresses you out.

But then we also have the sort of more future proofing stress things. So, you know, doing activities that we enjoy, looking after our emotional and social well-being having a you know a network around us and these can sort of buffer any future stresses as well so I think everyone should sort of try and explore the different tools that you know that there's a lot of science now to support and find the ones that are really applicable to their own lives. Yeah I completely agree with you and what of those things that people use kind of to de-stress is running and like there'll be people who find running like absolutely so stressful and then others who just like love doing it they'll go out after a really long day of work I do as

someone who runs I do find that I get like an element of like stress relief from it but thinking about exercise more widely, like people often say that intense exercise can actually dampen your immune system. But then overall, long term exercise, or regular physical activity is good for immune system. So what's the link? And how do we get that balance? Right? Yeah, I think that's a really good point. It's really interesting. There's sort of the older literature around exercise and the immune system that really pushed that message that too much exercise could suppress the immune system. And this was done looking at athletes who were going

to events where they're around large numbers of people where they can easily pick up germs. They're under a lot of stress because they're performing at an event and they were looking in their blood and measuring the different immune cells and what they found was that they would be more likely to pick up infections and that they would see a drop in the number of white blood cells when they measured them in their blood. But then a few decades later we sort of got a bit better at measuring immune function because not everything happens in the blood. In fact, most of the interesting stuff is happening in the tissues, but that's much harder to measure in people. You don't get so many willing volunteers letting you take biopsies from all sorts of parts of their body.

But they have since shown that this drop in immune cells from the blood in athletes when they were attending these large events or, you know, with a large training load, those cells were actually being redistributed to those body barriers, like the skin, the lung, the gut, allowing them to perform a better sort of surveillance function. So in fact, it seemed to enhance the immune system and the reason that they seemed to pick up more infections was probably just because they were around a lot of people but that being said there is a tipping point whereby some exercise tips into being too much and that seems to be when you don't properly refuel and recover so if you're overreaching which is pushing your body too

much without the appropriate balance particularly refueling with things like carbohydrates which seem to take the edge off the massive stress response that can happen from really heavy training loads so there's definitely a point where exercise can suppress your immune system but if you are recovering effectively and fueling all your work for your workouts then it shouldn't be something that's a problem no I agree with you there and I think the recovery point is really important because yeah we we see like athletes when they're going through like an intense training phase sometimes they do kind of intentionally overreach and push themselves harder but it's that fine balance where sometimes it's okay to slightly push yourself harder but when you're over training and under recovering then you not only perform poorly but then you can run into the problems of getting

sick and having injuries and things like that. But I think for everyday gym goers or runners and things like that, assuming they're not going, you know, max effort every day, exercise is going to strengthen your immune system in the long run. Oh, for sure. There's just so many ways in which exercise is important for immunity. Even just walking, the forces that are generated when you're doing something like walking it's having an effect on the bone marrow which is where our new immune cells are being produced and it's encouraging those fresh new immune cells to be set into the body and

they're going to replace the older ones that are more likely to malfunction and this keeps our immune age young and this is really kind of the crux of you know having a healthy lifespan is mitigating this natural aging which the immune system is very susceptible to it's anti-inflammatory you know and muscle mass is so important it's something I'm quite passionate about being someone in my 40s and I have lots of friends and people my age who I feel like grew up in that era where you did cardio to burn calories and nobody ever thought about protecting your muscle mass as you age but we know that this is a key marker of keeping your immune system young and rejuvenated as well. And when you're working those muscles,

they're also producing these myokines, these compounds that are rejuvenating the thymus gland, which is a gland in the neck that's responsible for producing our T cells. So it keeps the thymus gland young and that starts to shrink in our 30s and our muscles start to dwindle as well with every decade older that we get. So that's probably

my key way that I would encourage people to care for their immune system is by caring for their muscle mass on their body. I'm absolutely behind that message here. The other thing that I find really can set me off is lack of sleep. And I know there's really interesting research that like even one night of sleep can have a detrimental effect on your immune system so I'd love to chat about that next. Yeah for sure and as somebody who has suffered with insomnia in the past I have a lot of sympathy for anyone with sleep issues because it's it's no joke and it can be quite scary to know what a big impact sleep has on your well-being. And it is true that we see this drop in the function of particular cells called natural killer cells,

which are sort of the early antiviral cells from one bad night's sleep. So it is something that we should prioritize a little bit more. I think perhaps in the world we live in, we can quite easily just sail one more episode of Netflix, even though I'm really tired, sort of don't put sleep at the forefront. I think that sleep is a different phase of our immune system. During the day, we're out and about, we're more likely to bump into germs. So the immune system is kind of looking out for that. Whereas at night, it would be either fighting off an infection if you had one, or it would be doing more kind of housekeeping,

you know, like maintenance and repair work. So you need to have those two divisions, because if you're only fighting infections and not repairing, you know, then that's not going to turn out very well in the long term. But I think it is something that we just need to prioritise. There's also a special kind of lymphatic system that connects our brain to the rest of our body, which allows us to sort of clear out the gunk in our brain that builds up during the day. And this is really important for our cognitive health as well.

So I think there's so many levels in which sleep is important. And finding out what works for you, again, is going to be really individual. You need to have a good sleep hygiene, the consistent routine, but we also need to be making sure we get enough daylight during the day to really set that clock ticking from the morning to prepare for good sleep in the evening. And I think if you do have sleep problems, then it is worth going to speak to someone about it because no amount of sleep hygiene might be able to fix something that might have deeper roots. And again, as I said, I've had insomnia from when my children were born

due to a kind of hyper vigilance that I developed then so it's really something that gets support for. Yeah I think that's a really important message at the end because I can imagine listening to a podcast like this or conversations around sleep deprivation and health and if you're going through that period it can be quite daunting so yeah really really important message there. I guess to round up I would love to finish off with three questions that we finished with everyone but the the first one is what's the number one takeaway you want people to take from this podcast I think that consistency is key so I've mentioned lots of different inputs that we have control over to support our immune

system but it's kind of doing all the little things most of the time than doing all the things perfectly now and again and that's probably just comes from my own personal journey that's something I've learned you know going out and exploring all sorts of fancy supplements and treatments and things that are available actually just consistently doing all those foundational things puts you in a much better place in the long term yeah I think that goes for most things in life consistency and if you could go back and give your 18 year old self one piece of advice what would it be I would probably have to teach my 18 year old self to practice self-compassion. This is something I only

discovered much later in life, but did a lot of research about this and the immune system and found that when people are taught self-compassion techniques and they control for things like self-esteem, mental wellbeing, age, gender, body mass index, any post-traumatic stress, anything, they found that self-compassion could have actual tangible effects on the immune system that could be found in the blood. So the immune system was less pro-inflammatory, less unwanted inflammation, the cells were functioning better. It's quite liberating actually, because it's so easy to be hard on yourself and at the end of the day we are just all trying our best and doing the best with what we know yeah I love that I didn't know that but yeah that's a really good message and then the final one is what one book

would you recommend everyone reads and why obviously you can mention your own book but it would be great to have another one as well yeah Yeah, the one book that I read when I was writing my books that was very helpful was The Obstacle is the Way by Ryan Holiday. So he's an American guy who has sort of taken stoicism and made it really accessible. And it's kind of discussing why, how to sort of push through obstacles and barriers. And I think in life, there's always so many obstacles to doing the things that we want to do.

Yeah, I found that quite sort of comforting and his whole sort of messaging around Stoic philosophy was really useful. Amazing. I need to check that one out. It's good. Yeah, it's a great one. Just, you you know flipping an

obstacle into an opportunity and I often use um bits and pieces of his kind of philosophy when I'm teaching students because they're always coming at me with like oh it's so hard everything's hard and I'm like the obstacle is the way that's the point like you have to love the process and I have always gone into the opportunity I'm not sure if I've got them on board yet but yeah and so you do have your own book though which is great and so if people want to find that that's the book's titled immunity right yeah immunity the science of staying well and then the second one is coming out in February. And what's that? What's the title of the new book? It's how to build strong immunity. So the first one is kind of like a voyage through your immune system. And then the second one is how to develop your own blueprint for strong immunity, how to

personalize everything to you. So a lot of the things we discussed today is about how to find what works and what doesn't work. Amazing. amazing well thank you so much for your time today it's perfect kind of time of year to have this conversation it's been great thank you so much for having me so my takeaway from the podcast is that there is really no hierarchy of a good or a bad immune system and we all get sick sometimes no matter how healthy we may be. Our immune system is in fact a system and not a single thing which we can switch on and off or boost and really to function well it requires balance which we can help to support with nutrition, sleep, exercise, stress management and yes vaccination. A little

reminder that if you are enjoying the show, please consider leaving a five-star rating and a review so that we can reach as many people as possible and continue bringing you podcasts. That's all from me. See you again next time.