The Right Chemistry: Science shows carnivore diet is best left to lions

Montreal Gazette

18-07-2025

Jenny McCarthy, a former Playboy Playmate of the Year, is playing with science again. This time it is all about the 'carnivore diet.'
Her first foray into the scientific arena was in 2005, when her son was diagnosed with autism. She began to 'do her own research' that led to Dr. Andrew Wakefield's publication in the Lancet, a prime medical journal, linking the measles, mumps, rubella (MMR) vaccine to autism. That paper was eventually retracted, with Wakefield accused of submitting fraudulent data. His medical license in Britain was subsequently revoked, prompting a move to the U.S., where he found fertile ground for his anti-vaccine agenda.
McCarthy, with her then-boyfriend, Canadian actor Jim Carrey, became a vocal questioner of the safety of vaccines. She now insists, à la Robert F. Kennedy Jr., that she was never anti-vaccine; she was just in favour of delaying certain vaccines and reducing the 'toxins,' such as the preservative thimerosal that some contain. This flies in the face of scientific consensus. One would think the plethora of scientific studies published since Wakefield's deceitful paper that have found no relationship between vaccines and autism would have put the issue to rest, but sadly that is not the case.
Now McCarthy, 52, has opened another can of worms. Interestingly, the wriggling creatures would actually fit into the carnivore diet she currently advocates. Previously, she had been a vegan and even founded Formless Beauty, a 'vegan, cruelty-free, gluten-free' cosmetic company. Why? Because she was 'sick of putting toxic products on her skin.' No eyelashes made of mink fur for McCarthy! Her vegan eyelashes are made from synthetic fibres such as polybutylene terephthalate, polylactic acid or nylon. However, her vegan diet did not go well. 'I became so ill, like I was literally dying. I was exhausted, fatigued, I was a mess.' Then her 'functional medicine' doctor came to the rescue and suggested she try the carnivore diet. Joy now reigns supreme! She does not hesitate to reveal that as a vegan she was pooping every 14 days, but thanks to dining only on grass-fed meat, it is now a daily occurrence. We are all relieved to know this. Her acne has also cleared up and she says she feels like a 25-year-old.
What is this carnivore diet all about? Eat nothing but steak and eggs, snack on sticks of butter and abolish grains, fruits and vegetables. Why would anyone want to do that when a massive amount of research documents the benefits of a mostly plant-based diet? Because they have heard that feasting only on meat like a lion leads to weight loss, resolves arthritis, reduces inflammation, eliminates spikes in glucose, improves symptoms of irritable bowel syndrome, stabilizes mood and enhances cognitive function. Who says so? Nutritional luminaries like controversial Edmonton-born psychologist Jordan Peterson, his daughter Mikhaila (curiously named after Mikhail Gorbachev), podcaster Joe Rogan and former orthopedic surgeon and anti-vegan activist Shawn Baker. Keep in mind, though, that diets come and go, and similar claims have been made for the Keto, Cookie, Blood Type, Cabbage Soup, Sleeping Beauty, Cotton Ball, Vision, Grapefruit, Master Cleanse and Tapeworm diets.
The current advocates of feasting on red meat did not invent the carnivore diet. In the 18th century, Scottish military surgeon John Rollo concluded that a diet of meat was the answer to diabetes because meat contains no sugar. This was seconded a century later by Italian physician Arnaldo Cantani and American doctor James Salisbury, who claimed that beef drowned in gravy, the so-called 'Salisbury steak,' resolves various health issues. How and why Baker, with no expertise in nutrition, became the carnivore guru isn't clear.
What is clear is that the fad is not supported by evidence. Quite the contrary. The lack of fibre increases the risk of colon cancer, imbalances the intestinal microbiome, and can lead to explosive diarrhea. The International Agency for Research on Cancer (IARC) classifies red meat as 'probably carcinogenic to humans' and processed meat as 'known to be carcinogenic to humans.' A high-meat diet raises LDL cholesterol, the so-called 'bad cholesterol,' as well as blood levels of trimethylamine N-oxide (TMAO), a compound linked with cardiovascular risk. Meat also lacks vitamin C, magnesium and potassium, all found in plant foods. Then there is the issue of kidney stones. Too great a protein consumption can lead to both calcium-oxalate and uric-acid kidney stones, as exemplified by online influencer Eve Catherine, who ended up in hospital with severe pain after embarking on the carnivore diet.
People generally swallow the carnivore bait after having been seduced by the purported 'evidence' that scoots around the blogosphere, almost exclusively anecdotal. Mikhaila Peterson compellingly describes her arthritis symptoms vanishing. Blogger Patrick Ensley describes how eating a 16-oz steak, a pound of ground beef and a half-dozen eggs every day allowed him to lose 140 pounds, cured his snoring and eliminated his brain fog. In his videos, he warns people about eating vegetables like spinach, broccoli and kale because 'these produce plant defence chemicals, so they don't want you to eat them.' Nonsense!
Add to this the ripped body of Baker, Jordan Peterson's claims of relief of depression and Rogan speaking of putting on muscle and improving energy. These may be impressive anecdotes, but the plural of anecdote is not data. Neither do self-reported online surveys amount to evidence. Where we do find evidence is for the risks of excessive meat consumption and for the benefits of a Mediterranean type diet with lots of nuts, whole grains fruits, vegetables and little red meat.
There is one condition that might be helped by a carnivore diet. A case report in the journal Frontiers of Nutrition describes 10 patients with either Crohn's disease or ulcerative colitis going into remission after starting a carnivore diet, with symptoms only returning when patients diverged from their diet. It's a very interesting report that should prompt further studies, but should not be taken to mean that the carnivore diet is generally beneficial.
Baker asks: 'Why doesn't every wild animal that eats meat suffer from the chronic diseases modern humans face?' Maybe because the lion avoids the stress of having to listen to pseudo-scientific babble about diets by sleeping twenty hours a day.