Episode 97
Animal Protein and Cancer Risk
Animal Protein and Cancer Risk: What the Science Really Says
Recently, Mark Hyman posted on X (formerly Twitter) that a new study suggests eating more animal protein might actually lower your risk of cancer. The study he pointed to came from the NHANES dataset—a U.S. survey of diet and health. It sounded reassuring, but it doesn’t line up with the bulk of the evidence. Here is the story about Animal protein and cancer risk:
Let’s dig into what the science really shows.
Red and Processed Meats: Where the Risk Is Clear
If you want the strongest evidence, look at red and processed meats. Large prospective cohort studies and systematic reviews consistently show that higher intake of these foods increases cancer risk. The effect is clearest for colorectal cancer, but we also see it in breast, endometrial, and even lung cancer.[1–6]
How big is the risk? Recent meta-analyses and systematic reviews find relative risks (RRs) and hazard ratios (HRs) in the 1.10–1.30 range for the highest vs. lowest intakes. For example, a comprehensive meta-analysis reported that every 50–70 grams per day of red or processed meat increased colorectal cancer risk by 15–32% (HR 1.15–1.32).[3,5] Processed meat generally carries more risk than unprocessed red meat.[2–3,6]
That’s why the American Cancer Society recommends limiting red and processed meats. Their advice is clear: swap them out for fish, poultry, or legumes when possible.[15]
Fish: A Safer Bet
The data on fish tells a different story. Multiple studies and meta-analyses find a modest reduction in colorectal cancer risk with higher fish intake (SRR 0.94, 95% CI 0.89–0.99).[7–8] In fact, adding 50 grams of fish per day reduces risk by about 4%.
Pescatarian diets (no red meat, but including fish) show even more protection. Compared to meat-eaters, pescatarians had a 9% lower overall and colorectal cancer risk (RR 0.91, 95% CI 0.86–0.96).[9]
Poultry: Mostly Neutral
Chicken and turkey usually get lumped in with “animal protein.” But when you pull the data apart, poultry tells a different story. Most meta-analyses show a neutral or even slightly protective association with colorectal cancer (RR 0.79, 95% CI 0.63–0.99 for white meat).[10–12]
That said, a few studies hint at possible links with certain blood cancers, but those findings aren’t strong or consistent.[5,10] For most people, poultry is a much safer choice than red or processed meats.
Dairy: A Mixed Picture
Dairy is tricky. On one hand, milk and calcium-rich foods are consistently linked to a lower risk of colorectal cancer (RR 0.93, 95% CI 0.91–0.94).[4,13] On the other hand, high intake of milk or calcium may slightly increase the risk of prostate and endometrial cancers (RR 1.09–1.10).[13–14]
No consistent associations are found for breast or ovarian cancer. Cheese intake in particular may even have protective effects, but results vary.
Why the Confusion?
So why did that NHANES study Mark Hyman highlighted find a small reduction in cancer mortality with higher animal protein? A few reasons:
- NHANES relies on a single dietary recall—one snapshot in time that may not reflect long-term habits.
- It doesn’t separate red and processed meat from healthier animal proteins like fish or poultry.
- Residual confounding (differences in lifestyle factors that aren’t fully accounted for) may skew the results.
When you put NHANES side by side with larger, longer-term studies and meta-analyses, it looks like the outlier. The overwhelming weight of evidence shows that red and processed meats increase cancer risk, while fish, poultry, and some dairy products are safer or even protective in specific cases. Animal protein and cancer risk is positive.
The Bottom Line
Protein matters—but the source matters more.
- Red and processed meats: consistently linked to higher cancer risk
- Fish: modestly protective, especially for colorectal cancer
- Poultry: generally neutral, sometimes protective
- Dairy: lowers colorectal risk, but may raise prostate and endometrial cancer risk
The American Cancer Society sums it up well: limit red and processed meats, and lean into fish, poultry, beans, and plant-based proteins.[15]
References
[1] Rock CL, Thomson C, Gansler T, et al. CA Cancer J Clin. 2020;70(4):245-271.
[2] Abid Z, Cross AJ, Sinha R. Am J Clin Nutr. 2014;100 Suppl 1:386S-93S.
[3] Lippi G, Mattiuzzi C, Cervellin G. Crit Rev Oncol Hematol. 2016;97:1-14.
[4] Boada LD, Henríquez-Hernández LA, Luzardo OP. Food Chem Toxicol. 2016;92:236-244.
[5] Diallo A, Deschasaux M, Latino-Martel P, et al. Int J Cancer. 2018;142(2):230-237.
[6] Farvid MS, Sidahmed E, Spence ND, et al. Eur J Epidemiol. 2021;36(9):937-951.
[7] Poorolajal J, Mohammadi Y, Fattahi-Darghlou M, et al. PLoS One. 2024;19(6):e0305994.
[8] Vieira AR, Abar L, Chan DSM, et al. Ann Oncol. 2017;28(8):1788-1802.
[9] Parra-Soto S, Ahumada D, Petermann-Rocha F, et al. BMC Med. 2022;20(1):79.
[10] Nielsen TB, Würtz AML, Tjønneland A, et al. Br J Nutr. 2022;127(4):563-569.
[11] Bonfiglio C, Tatoli R, Donghia R, et al. Nutrients. 2025;17(8):1370.
[12] Wang F, Chandler PD, Zeleznik OA, et al. Nutrients. 2022;14(5):978.
[13] Willett WC, Ludwig DS. N Engl J Med. 2020;382(7):644-654.
[14] Watling CZ, Kelly RK, Dunneram Y, et al. Br J Cancer. 2023;129(4):636-647.
[15] American Cancer Society. Guidelines for Diet and Physical Activity for Cancer Prevention. CA Cancer J Clin. 2020;70(4):245-271.
Transcript
>> Dr. Terry Simpson: Eating more animal protein means less cancer.
Speaker:Well, so tweets Mark Hyman. You may have heard of
Speaker:him. He's a low carb enthusiast, a MAHA supporter,
Speaker:a supplement salesman, and now a nutrition
Speaker:revisionist. He wants you to believe that more
Speaker:animal protein lowers cancer risk, pointing to an
Speaker:outlier study that boils decades of flaw survey
Speaker:data into one thin gruel of a conclusion. This
Speaker:isn't science. It's the conjuring trick of a
Speaker:salesman. We would probably call it the arrogance
Speaker:of certainty. Without the burden of proof, Hyman
Speaker:waves away mountains of evidence from serious
Speaker:researchers, cancer epidemiologists on five
Speaker:continents because it doesn't suit his narrative
Speaker:or his business model. And so we're left with a
Speaker:choice. Do we follow the global consensus of
Speaker:scientists, or do we buy into the gospel according
Speaker:to a man whose medical insights can be measured in
Speaker:the half life of a supplement fad? I'm your chief
Speaker:medical explanation. It's Dr. Terry Simpson, and
Speaker:this is Fork U Fork University, where we make
Speaker:sense of the madness, bust a few myths, and teach
Speaker:you a little bit about food and medicine. Mark
Speaker:Hyman didn't start out as the the guru you see
Speaker:today. He was once a family doctor, then a spa
Speaker:doctor. Then he discovered something far more
Speaker:profitable than medicine. Selling supplements and
Speaker:pseudoscience. Out of that came functional
Speaker:medicine. What is functional medicine? Well, if
Speaker:you're a nurse, a dentist, or even a chiropractor,
Speaker:you can take a six month zoom course and suddenly
Speaker:call yourself a functional medicine doctor. You've
Speaker:probably seen the ads for the 300 tests they'll
Speaker:run on you for a few hundred dollars each. So why
Speaker:don't real physicians order 300 tests at once?
Speaker:Because modern medicine is based on history and a
Speaker:physical exam. If you shotgun three to 400 lab
Speaker:tests, you will always find some abnormalities
Speaker:statistically guaranteed. And once you've scared a
Speaker:patient with those numbers, you just happen to
Speaker:have the solution. A few hundred dollars worth of
Speaker:supplements every month. Maybe supplement really
Speaker:does stand for supplemental income. For a while,
Speaker:Hyman even carried the banner of the prestigious
Speaker:Cleveland Clinic. Why they eventually parted ways,
Speaker:no one knows. But what we do know is Hyman is
Speaker:camera ready. He has just enough jargon to impress
Speaker:the non doctor and his platitudes are exceeded
Speaker:only by his inability or unwillingness to read
Speaker:scientific research correctly.
Speaker:Which brings us to his latest misfire. On
Speaker:September 19, Mark Hyman tweeted that researchers
Speaker:analyzed the NHANES 3 data from 15,937 US adults
Speaker:followed for 20 to 30 years. According to Hyman.
Speaker:They found no link between animal protein and
Speaker:mortality and, um, even a modest reduction in
Speaker:cancer deaths with higher animal protein intake.
Speaker:Sounds like good news, right? Steak every night.
Speaker:But not so fast. NHANES is actually a valuable
Speaker:data set. It's helped us learn a lot about diet
Speaker:and health in America. It covers a large diverse
Speaker:population and tracks outcomes over decades.
Speaker:That's the good news. The bad news. The NHAIDES
Speaker:relies on a single 24 hour dietary recall. Asking
Speaker:someone once what they ate yesterday and then
Speaker:projecting that forward over decades. Worse, it
Speaker:lumps salmon, bacon, chicken, yogurt and steak
Speaker:into one bucket called animal protein. That kind
Speaker:of broad brush smooths over critical differences.
Speaker:Fish is not bacon, chicken is not salami, and milk
Speaker:is not steak. We have learned things from the
Speaker:NHANES study, yes, but anyone who reads these
Speaker:studies for a living will tell you the skill is
Speaker:knowing how to separate good data from junk
Speaker:analysis. And Hyman's is, unfortunately, junk
Speaker:analysis. So let's go to the evidence. When you
Speaker:turn to systematic reviews and large cohort
Speaker:studies, the picture becomes clear and far more
Speaker:precise than the NHANES snapshot. Let's look at
Speaker:red and processed meats. Multiple independent
Speaker:studies across different populations consistently
Speaker:show the same thing. Higher intake means higher
Speaker:cancer risks. Add 50 to 70 grams a day of red or
Speaker:unprocessed meat and colorectal cancer risk rises
Speaker:15 to 32%. Processed meats carry an even greater
Speaker:risk. Let's go to fish. Several carefully
Speaker:separated analyses show that 50 grams a day lowers
Speaker:colorectal cancer risk by, uh, 4%. Pescatarians,
Speaker:those who eat fish predominantly as their meat
Speaker:source, have roughly, uh, a 9% lower overall
Speaker:cancer risk than regular meat eaters. Poultry?
Speaker:Well, independent studies show that it's neutral
Speaker:to maybe even slightly protective. Unlike red
Speaker:meat, poultry hasn't been linked to higher
Speaker:colorectal cancer risk when carefully analyzed.
Speaker:What about dairy? You know, Greek yogurt? Large
Speaker:cohorts demonstrate that milk and calcium lower
Speaker:the colorectal cancer risk. But at very high
Speaker:intakes, dairy, especially milk, has been linked
Speaker:to increased risk of prostate and endometrial
Speaker:cancer. Now let's just contrast this with plant
Speaker:protein. And the data here is so remarkably
Speaker:consistent. Higher plant protein is associated
Speaker:with a lower risk of overall cancer incidence and
Speaker:cancer mortality, particularly when plant protein
Speaker:replaces animal protein, especially red and
Speaker:processed meats. Multiple prospective cohorts,
Speaker:meaning we take a group of people and we follow
Speaker:them over time and, and meta analysis, meaning
Speaker:we've taken a lot of these studies together, show
Speaker:that plant protein is Inversely associated with
Speaker:all cause cardiovascular mortality, meaning it's
Speaker:heart healthy. And when we substitute animal
Speaker:protein with plant protein, it reduces the overall
Speaker:risk of total and site specific cancers,
Speaker:especially colorectal. Now here's the key. Every
Speaker:major cancer body, whether it's the American
Speaker:Cancer Society, the World Cancer Research Fund,
Speaker:the European Union, or cancer research institutes
Speaker:in Canada, Australia and beyond, document these
Speaker:same trends. The problem isn't with protein
Speaker:itself. It's with lumping it all together, as N.
Speaker:Hayden's does. That fuzzes the picture. But when
Speaker:you separate the sources, as these independent,
Speaker:carefully done studies have, the information
Speaker:becomes crystal clear. Red and processed meat
Speaker:increases cancer risk. Fish tends to protect.
Speaker:Poultry is neutral. Dairy is mixed. And plant
Speaker:protein is protective, especially when it replaces
Speaker:red and processed meats. Now, Hyman writes, I
Speaker:Recommend Aiming for 4 to 6 ounces of high quality
Speaker:animal protein per meal, twice a day. Now, that
Speaker:might sound like sensible advice, but this isn't
Speaker:what cancer prevention is made up for. This is
Speaker:bodybuilding math dressed up as medicine. Follow
Speaker:that prescription, literally, and you're eating
Speaker:steak at lunch, steak at dinner, with eggs,
Speaker:poultry and dairy filling in the gaps. That's not
Speaker:building resilience, that's building cancer risks.
Speaker:Multiple cohort studies show that diets highest in
Speaker:red and processed meats, the very food his
Speaker:prescription promotes, carry the highest rates of
Speaker:colorectal, breast and endometrial cancer
Speaker:substitution. Studies are clear. Replace red meat
Speaker:with plant protein or fish and the risk goes down.
Speaker:Follow his advice and it goes up. And here's the
Speaker:kicker. There is no cancer society, no cardiology
Speaker:body, no public health organization on earth that
Speaker:recommends 1 gram of protein per pound of body
Speaker:weight. Every major health body recommends the
Speaker:opposite. Cut red and processed meats and replace
Speaker:them with other healthier sources. Now contrast
Speaker:that with the Mediterranean diet, the most studied
Speaker:diet for longevity. It allows up to 4 ounces of
Speaker:red meat in a day or less. And people who follow
Speaker:it don't just live longer, they live healthier
Speaker:with lower cancer and heart disease rates. So when
Speaker:Hyman prescribes his four to six ounces twice
Speaker:daily, the question is, is he reading the data or
Speaker:is he just selling to the low carb crowd? Because
Speaker:it isn't medicine, it's marketing.
Speaker:Next on his thread, Hyman advises, and I quote,
Speaker:choose grass fed pasture, raised meat, organic
Speaker:poultry and eggs, wild caught fish. They're higher
Speaker:in omega 3s, B12, zinc, and lower in hormones,
Speaker:antibio and inflammatory fats. Now that sounds
Speaker:great, but here's the truth. The difference
Speaker:between grass fed and corn fed beef is minimal
Speaker:when it comes to cancer risk. Grass fed beef may
Speaker:have a touch more Omega 3s, but it's still red
Speaker:meat. It is still produced in the same DNA
Speaker:damaging compounds when grilled or smoked. And the
Speaker:biggest difference? Taste. Grass fed beef often
Speaker:tastes grassy or gamey. Corn fed beef is richer,
Speaker:marbled. And frankly, I'll admit I prefer the
Speaker:taste of corn fed beef. But preference doesn't
Speaker:change cancer data. If you want real nutritional
Speaker:benefit, you'd be far better off eating farmed
Speaker:fish other than any kinds of beef. Fish has more
Speaker:omega 3s, fewer carcinogens, and protective effect
Speaker:against colorectal cancer. Choosing grass fed over
Speaker:corn fed steak isn't a health choice. It's a
Speaker:palate choice. So when Hyman pitches quality meat
Speaker:as though a, uh, marketing label erases decades of
Speaker:cancer research, he isn't giving medical advice,
Speaker:he's selling a lifestyle brand. Hyman also wrote,
Speaker:quote, for decades, scientists have thought high
Speaker:protein raised cancer risk by raising IGF1. But
Speaker:this study showed there was no link between IGF1
Speaker:and mortality. This is a classic sleight of hand,
Speaker:IGF1, which is a pathway. It's not the whole
Speaker:story. But cancer begins with DNA damage. When red
Speaker:meat is processed, it forms nitrates and nitrites
Speaker:that become carcinogens. When red meat is grilled
Speaker:or charred, it produces heterocyclic amines and
Speaker:polycyclic aromatic hydrocarbons. These chemicals
Speaker:damage DNA directly. And if your repair systems
Speaker:fail, mutations build and cancer can begin. So to
Speaker:say no IGF link means no risk is like pointing at
Speaker:the matchbook and ignoring the bonfire. The risk
Speaker:isn't theory, it's chemistry. Hyman closes with.
Speaker:Moderate intake of animal protein does not raise
Speaker:risk. Prioritize nutrient dense sources, balance
Speaker:with colorful plants, and lifestyle factors like
Speaker:smoking and inactivity matter more than protein
Speaker:intake. Sure, plants help. Fruits, vegetables, and
Speaker:whole grains do mitigate some of the cancer risk
Speaker:of unprocessed red meat. That's good news. But
Speaker:plants don't cancel out bacon. A salad with your
Speaker:hot dog doesn't erase the hot dog. And I love a
Speaker:Chicago style hot dog that has lots of vegetables
Speaker:on it. And relish. It's delicious. But smoking
Speaker:inactivity are stronger risk factors than diet.
Speaker:But that doesn't mean diet doesn't matter. Smoking
Speaker:is worse than asbestos, too, but that doesn't make
Speaker:asbestos safe. Cancer risk is cumulative. Every
Speaker:preventable risk counts. So when Hyman wraps
Speaker:himself up in a platitude about colorful plants,
Speaker:he's not doing science, he's doing spin. So here's
Speaker:the bottom don't be fooled by viral nutrition
Speaker:tweets. The overwhelming evidence shows that red
Speaker:and processed meat raise cancer risk, fish helps,
Speaker:poultry is neutral, dairy is mixed, and plant
Speaker:protein is protective, especially when it replaces
Speaker:red and processed meats. And as much as I would
Speaker:love to sit down and have a big steak every night,
Speaker:I don't because I believe the data. And the data
Speaker:says less red and processed meat, more fish, more
Speaker:plants, and better health. For references and the
Speaker:full breakdown, check the blog
Speaker:post@yourdoctorsorders.com and 4Q.com Please
Speaker:subscribe to this podcast, share it with friends
Speaker:and help spread the evidence, not the hype. This
Speaker:podcast was distributed by our friends at Simpler
Speaker:Media and my good friend the cod pod God, Mr. Evo
Speaker:Terra. And remember, while I am a board certified
Speaker:physician, I am not your physician. Please talk
Speaker:with your board certified doctor, not a
Speaker:chiropractor, certainly not a functional medicine
Speaker:doctor and a registered dietitian before making
Speaker:any big changes to your diet. Yes, I still eat red
Speaker:meat. I sometimes have tofu. I probably should
Speaker:have it more often. And you should too. Oh, and
Speaker:here's a culinary tip. When you like your steak,
Speaker:marinate it in some rosemary that actually cuts
Speaker:down on some of the heterocyclic amines and
Speaker:produces less carcinogenic compounds when it's
Speaker:grilled. Culinary tip for the day from the doctor.
Speaker:Alright everybody, have a good week.
Speaker:All right? Ivo, after all this protein talk, fish
Speaker:tacos or bacon cheeseburger? Which one's going on
Speaker:your plate? Me. I kind of like the fish tacos
Speaker:around here. They're freaking delicious.
Speaker:>> Speaker B: Oh yeah, fish tacos have been my go to for quite a
Speaker:while now. They're amazing. Speaking of which, I
Speaker:didn't edit out when you mistakenly called me the
Speaker:cod podfather.
Speaker:>> Dr. Terry Simpson: You know, because I like Code M.
