Episode 89 Summary
- Should we be worried about getting cancer from eating red meat? A 2018 report from the WHO (World Health Organisation) basically stated that red meat was a carcinogen. However, when delving into the report, Dr Alex Petrushevski found that the association between red meat and cancer is incredibly weak. The report was further flawed as the WHO considered a serving of red meat to be anything with red meat, for example a Big Mac with fries and Coke, ignoring the fact this also contains sugar, processed seed oils, etc. As the data used to form this conclusion was junk, it follows that the conclusion itself is junk.
- Red meat vs processed red meat - whilst there is a little bit more concern with the curing agents and nitrates used in processed meats and their effect on the gut microbiome, even then the association is really weak. Whilst fresh meat is always better, more nutritious, and nutrient-dense than processed meat, a little bit of bacon or smoked salmon now and again is unlikely to be a major factor in someone's health.
- The reason that people that have conditions such as obesity or insulin resistance, metabolic syndrome, or type two diabetes, are at a higher risk of cancer, is predominantly because of the effects of insulin. Insulin encourages cell growth and the more growth you have, the more chance you have for something to go wrong when a cell divides. Once you've got a cancer cell, there's evidence that insulin can act as a stimulant to propagate that cell to grow faster as well.
- For certain cancers, especially the female-centric ones, breast cancer and endometrial cancer, having higher levels of insulin and being obese actually increases oestrogen levels and these cancers tend to feed on oestrogen as well. So for those specific ones, the higher oestrogen levels do contribute to the increased risk of cancer.
- There are also a litany of effects on the gut microbiome that come when you're metabolically unwell or when you're obese and they seem to have some flow on effects when it comes to either increased risk of cancer or an increased risk of progression or bad outcomes once you have a cancer. So there's many different pathways, but for many people, the insulin is the root cause.
- A Ketogenic diet for cancer - there is emerging evidence that cancer cells don't metabolise ketones very well and are much more reliant on glucose. So there may be some anti-cancer effect from starving the cancer cell of glucose. However, it is still very much in the investigational stage, so we can't say that a ketogenic diet is going to be a cure for cancer. However it is something you could consider in addition to your standard treatments, your surgery, your chemotherapy, your radiotherapy, as this is very much an active area of research.
- Stress management and meditation are helpful for cancer and research on cancer survival shows that people who survive their cancers are able to maintain good stress levels and good self-care. As cortisol has direct pathways in that metabolic process, it is very helpful to manage your stress and keep those cortisol levels lower.
- Nutrition and Western medicine complement each other, it is not a case of picking one or the other. Medication and nutrition when implemented together can have a synergistic effect where the combination of both is much greater than the sum of the parts.
- The importance of non-scale victories - sometimes people can be disheartened because they haven't lost as many kilos as they would like, but they are oblivious to other benefits such as their blood pressure is now lower, they're sleeping better, or they are able to walk pain free. These non-scale victories are important because they make you happier, reaffirms what you're doing, and keep you looking at the important things in life.
Dr Alex Petrushevski graduated from the University of Tasmania in 2008, attaining Honours in the MBBS. He has worked in various teaching hospitals in 2 states, including working for several years within Sydney Cancer services, and had his research published in an International journal during this time. His postgraduate qualifications include the Fellowship of the College of General Practitioners and the Diploma of Child Health from Sydney University and additional training in low carbohydrate nutrition via the Nutrition Network.
He currently works in general practice in addition to practising within Sydney Low Carb Specialists. He is passionate about preventative health, improving the lifestyle of his patients and treating chronic diseases without medication if possible. Having seen the immense benefits low carbohydrate nutrition has provided for many of his patients in general practice he is keen to share this exciting cutting edge medical therapy with as many patients as possible.
You can watch Alex's presentation on “Red meat and cancer” here
Show notes:
Can low carb help prevent cancer?
Dr Mary Barson: Hello, my lovely listeners. I'm Dr Mary Barson.
Dr Lucy Burns: And I'm Dr Lucy Burns. Welcome to this episode of Real Health and Weight Loss.
Dr Lucy Burns: And I'm Dr Lucy Burns. Welcome to this episode of Real Health and Weight Loss. Good morning, lovely listeners, it's Dr Lucy here today and I am without Dr Mary, in fact I have a fabulous guest in store for you. I always love talking to other doctors and this is another Australian doctor based in Sydney. His name is Dr Alex Petrushevski and he runs the Low Carb Specialist Clinic in Sydney. Welcome to the podcast, Alex.
Dr Alex Petrushevski: Hi Lucy, thank you for having me.
Dr Lucy Burns: You're welcome. You are a wealth of knowledge when it comes to many things in the low carb sphere and Alex and I first met at a low carb conference many years ago and I heard him speak on red meat and the cancer risk, which is something I think we'll touch on today. But Alex has a special interest really in lots of things to do with cancer. So, I think you know, cancer is never a topic that people love talking about, but it's very common, and most of us will know somebody who at some stage either has had or will get cancer. So here's, I think a good topic for us to kind of get our teeth into. So Alex, first of all, I would love if you can, I know you did, you did a brilliant talk and I totally loved it and it's, it's up, it's probably up on YouTube under Low Carb Down Under, so you can always google him, folks. But if you could perhaps just give us a little summary on that, because I know everybody, everybody is worried about red meat and cancer. So can you give us a few, just sort of a summary tips, I guess on that?
Dr Alex Petrushevski: Sure. So yeah, so the talk you're referencing I did I think in 2018 and it was really in response to a report that was published by the WHO, basically stating that red meat was a carcinogen. And so it came out then, got lots of press, and obviously scared a lot of people away from eating red meat at the time. The data they used to come to this conclusion was basically based on years and years of observational data and food questionnaire studies, which for anyone who's delved into nutritional science, they quickly find is really fraught with inaccuracy. It's caused a lot of nutritional calamities in our society when it comes to the theory of saturated fat, or the theory of cholesterol and eggs, or all sorts of things like that. So when you really look at the document the WHO put out, it reads like a political document. So the researchers had a bias going in, they essentially tried to prove it and they did it based on some pretty weak statistical evidence. So when I first started looking into it in more depth, because it was relevant to my practice, I don't want my patients eating red meat if it's going to give them cancer, when I really delved into it, the association was incredibly weak. So as part of their meta-analysis that they quoted, they quote a relative risk, which is basically a measure of how much someone's risk is going to be greater if they're doing a particular behaviour, or if they're taking a particular drug, compared to someone who's not. So the relative risk for being a meat eater was a 1.18 times increased risk of getting bowel cancer. That was pretty much the headline stat. So basically, for every 1 cancer that a non-red meat eater gets, you're gonna have 1.18 bowel cancers in red meat eaters. Now to put that into perspective, if you're a smoker, your relative risk of having lung cancer is between 10 to 30. So, way, way, way bigger than 1.18. So, and even at 1.18 is dubious, at best, really. So as a general rule in epidemiology, if the relative risk is under two, then it's considered fairly weakened and very, very likely caused by other confounders. And we see this in so much research that's done, you know, people that in the past have eaten more red meat, they're more likely to be people that ignore other health advice. They're more likely to drink alcohol, they're more likely to smoke, they're more likely to not exercise, all these other things. And in these food questionnaires, red meat is considered basically anything with red meat. So a Big Mac with fries and Coke is considered a serving of red meat, even though we all know that it's not just the red meat in that burger, it's the sugar, it's the bun, it's all the processed seed oils, everything else. So the data used to come up with these conclusions is just junk, so no surprise, the conclusion is junk.
Dr Lucy Burns: I know, it's just so disappointing I think when you've got a body like the WHO, who most people would, you know, consider respectful compared to say, a tabloid journal like The Herald Sun, and they're essentially promoting a similar concept. I think, was I reading, or we talked about it when there was, again some sensationalised headlines about eggs causing diabetes in Chinese women. And it turned out that you know, anything with eggs in it, including cakes and pancakes and all of the desserts include, that counts as eggs.
Dr Alex Petrushevski: Yeah, it must be the eggs.
Dr Lucy Burns: Yeah, so ridiculous. Do you have any thoughts on the difference in the types of red meat? Like there's red meat, and then people talk about processed red meats. What are your thoughts on those?
Dr Alex Petrushevski: Yeah, yeah. So that same report looked at processed meat as a separate sort of category and the data for processed red meat was a little bit stronger. But even then, it's pretty weak and once again, you have to tease out what's actually causing the trouble. So people eat processed meats, they often eat them with other things in fast food, or with sugary drinks and all that sort of thing. So, even the processed meats, not one homogenous group of foods. There's a little bit more concern with processed meats when it comes to the curing agents and nitrates and potentially some effects on the gut microbiome, but even then the association is really weak. So what I would normally tell people is fresh meat is always better, it's always going to be more nutritious, more nutrient-dense than processed meat. But at the end of the day, a little bit of bacon or smoked salmon here and there is unlikely to be a major factor in someone's health or lack of.
Dr Lucy Burns: Yeah, absolutely. And I think, you know, there's also some, again what people lump into processed meats, so hot dogs, generally, would be a pretty sort of low-quality version of processed meats. And Kabana, it varies, you know, not all Kabanas are equal. So I think probably like you we are big advocates of reading the nutritional labels so that you know exactly what you're buying, and not just assume that the front star or, you know, bright coloured label actually tells you what it really is.
Dr Alex Petrushevski: Correct. When I was doing research for that presentation, I looked at the, just the standard beef jerky in Coles and I was shocked to find it's actually 20% sugar by weight. So you know, even something as, you would think would not have loads of sugar like that has huge amounts, so.
Dr Lucy Burns: Yeah, absolutely. And yeah, that's the classic one and again, you just don't know because there are, there is beef jerky that doesn't have sugar. But unless you either research or find somebody who's done all the research for you and, or you just look it up. But I think from memory, there's currently no jerky at Coles that doesn't have sugar.
Dr Alex Petrushevski: None that's worth buying, no.
Dr Lucy Burns: No. And it's the same with you know, people are buying pork crackling, or pork scratchings or pork something or others and a lot of them have sugar or seed oils or rice flours. It's not just pork crackling.
Dr Alex Petrushevski: Correct.
Dr Lucy Burns: I think you probably do this, but Mary and I often say, you know, it's pretty hard to find shortcuts. There's a few shortcuts around, but a lot of them aren't real. They're not really shortcuts.
Dr Alex Petrushevski: Yeah, absolutely. So we all, in our clinic we often have sort of products that we trust or products we'd recommend that are packaged, but we generally tell people, you're unlikely to find them in Coles and Woollies. So usually would say the best ones to get are the ones you get online, so we try and encourage people to plan ahead, and so order them and stock up so that way they're around.
Dr Lucy Burns: Yeah.
Dr Alex Petrushevski: And we find that's really useful because especially for patients who are trying to lose weight or trying to get control of their food, you want, you want to have options around especially when they're, when they're stressed or when time is poor. So that way there's, the road to a good decision is easier to get to.
Dr Lucy Burns: Yes, yes. Make the right thing easy, make the wrong thing hard. One of our favourites. So Alex, I'd love to hear your take a bit more on cancer. So there's lots of, there's lots of evidence and it's tricky and I'm going to caveat with this, this phrase that people can be shamed by the medical profession for having obesity. And when I say the word, that obesity increases your risk of cancer, this is not about making people feel bad. This is about explaining why. What is the driver of obesity that increases your risk of cancer? So that's what I'd love you to explain to our listeners today.
Dr Alex Petrushevski: Sure. So that is a complex question that comes with a complex answer. So I guess from the outset, cancer is not just one illness, it's a variety of different conditions. So it's quite mixed and varied, but there are some commonalities amongst them all. So the reason that people that have obesity or insulin resistance, metabolic syndrome, type two diabetes, all of these conditions that sort of sit on one continuum, the reason they're at higher risk of cancer is, is predominantly because of the effects of insulin. So insulin is a growth factor, it encourages cell growth, so the more cell growth you have, the more chance you have for something to go wrong when a cell divides, so. And then once you've got a cancer cell, there's evidence that insulin can act as a stimulant to propagate that cell to grow faster as well, alright. So that's the primary reason why insulin resistance or high insulin levels in the body can precipitate cancer. For certain cancers, especially the female-centric ones, so breast cancer and endometrial cancer, having higher levels of insulin and being obese actually increases oestrogen levels and these cancers tend to feed on oestrogen as well. So for those specific ones, the higher oestrogen levels do contribute to the increased risk of cancer. And then somewhat separately from all of this, you've got a litany of effects on the gut microbiome that come when you, when you're metabolically unwell or when you're obese. And they, they seem to have some flow on effects when it comes to either increased risk of cancer or an increased risk of progression or bad outcomes once you have a cancer. So there's many different pathways. But for many people, the insulin is the, the root cause as with so many things.
Dr Lucy Burns: Yes, pesky insulin. It is, you know we talk about it a lot, it's responsible for a lot of things. But the good news is that when you lower your insulin, you get the benefit of improving all of these things, not just one thing. That's why, you know, low carb is more than just weight loss, it really is about improving your metabolic and your whole health. So when you know, and this happens, you know this doesn't happen infrequently, but if somebody develops, you know they've got a diagnosis of cancer, and it could be bowel cancer, or lung cancer or something along those lines, they'll often say, you know, they'll often be referred to a dietitian and generally speaking, we know that most dietitians follow the standard Australian guidelines. But what would you be recommending that people would eat for their health?
Dr Alex Petrushevski: So it really depends on the clinical situation. So for some patients, when they're diagnosed they're already significantly malnourished, whether that's because they've got a cancer in their gut and their gut's been not working well for some time, or if they've got multiple sites of cancer they may have something called cachexia, which in essence is a loss of muscle mass, loss of lean mass, because the cancer is using that, that tissue as fuel. So often when cancer patients see a dietitian, a dietitian's primary concern is not losing weight, because often treatment is associated with weight loss, nausea, not eating properly and then the cancer on the other end of things is also eating into that lean tissue mass. So they're, they're very wary about restrictive diets during this time and that's, and that's fair enough. When we however look at the biochemistry of what cancer cells use for fuel, there's some emerging evidence that cancer cells have very defective mitochondria, which are basically little pieces of the cell where the energy is formed. That's like your engines of your cells. And so there's emerging evidence that cancer cells, they don't metabolise ketones, or fatty acids very well. So the cancer cells are much more reliant on glucose. So there is some emerging research that if you can starve the cancer cell of glucose or in essence, create a hostile environment for the cancer cell by having lots of ketones and not much sugar around, then that may be something you can leverage to your advantage. So there may be some anti-cancer effect with that. Now, I have to sort of pause there and let your listeners know that this is still in investigational stage, so we can't say that a ketogenic diet is going to be a cure for cancer. So nobody should be ignoring the advice of their oncologists and jumping into a ketogenic diet just for that reason, but as an adjunct, so in other words, as something you could consider in addition to your standard treatments, so your surgery, your chemotherapy, radiotherapy, this is very much an active area of research.
Dr Lucy Burns: Well, I think that's a great point and you know, it certainly gives an alternate view to some people who I know who go on massive juice cleanses when they get diagnosed with cancer. And that was certainly made very popular probably, maybe 20 years ago now, but you know, what are your thoughts on that?
Dr Alex Petrushevski: I would be very wary of that. I mean, I know that there are some anecdotal reports out there of people doing all sorts of things and supposedly having success, but I think from a, from a biochemistry point of view, yes, you are starving the body, or you're starving the cancer, but you're also starving the body when you do that. So juice is not going to have much protein, so that whole cancer, cachexia, lean muscle mass loss issue is going to be even more exaggerated with people who are going on starvation diets like that, so. So I think rather than that you want to be doing something where you're still fuelling the body, so the other tissue that still needs to get energy, especially if it's coming under assault from you know, toxic treatment like radiotherapy, chemotherapy, it needs energy to heal itself as well. So yeah, I'd be a bit wary about starvation diets or juice cleanses. I don't think there's any strong evidence that they're going to be particularly useful.
Dr Lucy Burns: No. And in fact, I would go further to say they're probably dangerous because the thing we know that juice has high level of fructose but also glucose. So not only is it going to worsen any potential metabolic syndrome, but put a lot of strain on the liver, which is already now going to be under massive strain dealing potentially with chemotherapy or some sorts of treatments. I think one of the things that has been known to be very helpful for cancer outside of nutrition is certainly stress management, meditation and many of those therapies which, you know lovely listeners, Dr Mary and I love talking about, but they're certainly also had some proof in, in helping somebody and certainly not harming somebody.
Dr Alex Petrushevski: Correct, yep. And a lot of the cancer research on survival looks at that as well. So people who survive their cancers are able to maintain good stress levels, good self-care, they're more likely to do better in the long term as well.
Dr Lucy Burns: Which as we all know makes complete sense because stress is all about cortisol. Well, it's not all about cortisol but it is, there is a huge component of cortisol in it, which has direct pathways in that metabolic process. So if you can manage to learn how to I guess, manage your stress, and keep those cortisol levels lowish, lower, then that's going to be lovely and helpful.
Dr Alex Petrushevski: Correct, yep.
Dr Lucy Burns: So Alex, do you see patients in your clinic with cancer?
Dr Alex Petrushevski: We do. It doesn't make up a large proportion of what we see in our clinic, but we do see some cancer patients. Often people will come to us either in the setting of having a stage four or an incurable cancer, sadly, and where they've exhausted their other options, or they're looking at starting potentially curative treatment for a curable cancer and looking to, to help optimise either their tolerance of treatment, and there's some evidence that ketogenic diets can help with you know, reducing chemotherapy nausea, or just to maintain their metabolic health through the journey. So that's usually the setting that we will see patients. We're very clear with the patients that in terms of a standalone cure, there's not enough evidence that ketogenic diets can help with that, but as something to add on to standard treatment, I think it's something that's potentially beneficial. And as I mentioned before, is a very active area of research at the moment.
Dr Lucy Burns: Wonderful. And I think it is important to note, Dr Mary and I also believe that, you know, lifestyle medicine, nutrition, it's not an either or. You don't have to just do nutrition, and therefore you can't do normal standard Western medicine. And you don't have to just do standard Western medicine, which means you can't address your nutrition. Like they, they complement each other. They're not a, it's not a dogmatic, if you do this, you can't do that.
Dr Alex Petrushevski: Absolutely, can't agree more. And there's certainly many strategies you can implement that really leverage both together that offer a synergistic effect where the combination of both is much greater than the sum of the parts.
Dr Lucy Burns: I love that little saying, that's a very good one and in fact, I'm going to do a complete 180 there and just suggest that, you know, for lots of things we do in medicine, it's exactly that. Like, you know, managing hypertension or high blood pressure, for some people, they still need medication, but optimising their lifestyle improves all sorts of things.
Dr Alex Petrushevski: Yes. Often patients will come for the weight loss or come for some other reason and then leave with a handful of other benefits as well and I'm sure you see that in your clinic as well.
Dr Lucy Burns: Absolutely. It's interesting, in lots of spheres, it's a, you know there are some people who believe that if you can't manage your metabolic disease by lifestyle, that you've somehow failed, and it's really so far from the truth. At the end of the day, we're wanting to, you know, I guess prevent the devastating consequences of metabolic disease. Low carb is one of those tools, it's a fantastic tool, but for some people, it's not enough.
Dr Alex Petrushevski: Absolutely, and we see a lot of that in our clinic as well. I think in many ways social media is beneficial, it's been a great help for a lot of people when they're, with their health, but it does come at a cost, especially when online you see a lot of the biggest success stories. So just by human nature, the people who get the best results are going to be the loudest about what they've done. So people will often end up comparing themselves to either their friends or other people online and what we have to tell people is, “You gotta run your own race”. You know that person you see online, might not have a thyroid condition. They might not be running on a sleep debt because they've got three young kids. They might not be dealing with other issues that make, make them achieving their health goals harder. So you have to compare yourself to the you of yesterday, or you of last month, rather than to someone else.
Dr Lucy Burns: Absolutely. I think there's many people that say, “Comparison is the thief of all joy”, and it is totally true. And that social media only gives you the highlight reels. Nobody puts their failures, well, some people do, but not many. Most people don't, they just put their wins up and they curate. It's very curated. So it is hard, because you're right, it is our human nature to compare part of our, the fabric of our society, but so dreadfully unhelpful.
Dr Alex Petrushevski: Yes, and it means that patients just often miss those non-scale victories that they could be focusing on.
Dr Lucy Burns: Absolutely.
Dr Alex Petrushevski: So it's not uncommon that someone will come into the clinic really disheartened because they've only lost a kilogram of weight in, you know, in three months, or whatever it might be, but they're oblivious to the fact their blood pressure is coming down, or they're sleeping better, or they're, or they're able to walk because their knee doesn't hurt anymore and all these other side benefits. We really try and tell patients to look out for these non-scale victories, because if you can see them, it makes you happier, it reaffirms what you're doing, and it keeps you looking at the important things in life.
Dr Lucy Burns: Absolutely. And I think, you know, the scales are like a frenemy, they're really sneaky. You know, we spend quite a bit of time encouraging people to put them away, because they are probably the biggest undoer of motivation. And you know, you can be thinking that you're going along really well, and you hop on the scales, and you go, “Oh, my God, I've put on some weight”, and suddenly you just, the whole thing, you throw the whole thing in. You just suddenly go, “This isn't working. I'm not doing this anymore. I don't know why I'm doing this. I'm wasting my time. I'm wasting my money”. And all of a sudden, you just give up and go back to your old life, which is guaranteed, we know guaranteed, to put on more and more weight.
Dr Alex Petrushevski: You could argue the cortisol rise from looking at the scales is going to be more counterproductive than anything else.
Dr Lucy Burns: Absolutely, oh I like that one. That's a good reframe. Wonderful. Alright, so Alex, if people wanted to get in contact with you, and I know your lovely wife is also a low carb doctor and listeners she's coming on the program soon, too, so she'll be talking all things, we've got some female hormone chats, coming up with Deepa, but if people wanted to get in contact with you, how do they go about that?
Dr Alex Petrushevski: Sure. So our clinic's called Sydney Low Carb Specialists. We're located in Castle Hill in Sydney. Our website address is www.sydneylowcarb.com.au. We've got a presence on social media, usually on Instagram, but also on Facebook. So they're where you can find us. Yeah, so if anyone wants to reach out then feel free.
Dr Lucy Burns: Yes. And google you to have a look at your fabulous talk from Low Carb Down Under under Alex Petrushevski. It'll be in our show notes. So you don't have to worry people if you can't spell it. It's a long name, but I will have it spelt correctly and a link to that, to his YouTube talk and to the low carb clinic.
Dr Alex Petrushevski: Thank you so much for having me on, Lucy.
Dr Lucy Burns: Fantastic. Thank you so much for being on the program, Alex. I think the listeners will have got a wealth of information and honestly people if you have any concerns about your health, go and see your doctor. It's really, really important. All right, have a wonderful, wonderful week and we will talk to you next time. Bye for now.
Dr Lucy Burns: So my lovely listeners, that ends this episode of Real Health and Weight Loss. I'm Dr Lucy Burns.
Dr Mary Barson: And I'm Dr Mary Barson. We're from Real Life Medicine. To contact us please visit https://www.rlmedicine.com
Dr Lucy Burns: And until next time, thanks for listening. The information shared on the real health and weight loss podcast, including show notes and links provides general information only. It is not a substitute, nor is it intended to provide individualised medical advice, diagnosis or treatment, nor can it be construed as such. Please consult your doctor for any medical concerns.
