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Taking a Bite Out of the Carnivore Diet

The Carnivore Diet is an extreme eating regimen that includes exclusively animal products.

Breakfast: Bacon with eggs 

Lunch: Ground beef cooked in tallow 

Dinner: Venison steak with a side of bone marrow 

It sounds like the diet of someone yearning for double-bypass surgery. In reality, it’s just one day of the Carnivore Diet, an extreme eating regimen that includes exclusively animal products. While your intuition might tell you that the Carnivore diet surely can’t be good for you (where are the veggies??), celebrities like Joe Rogan have touted it to millions of listeners. Rogan has claimed that the Carnivore Diet has helped him lose weight, reduce aches and pains, improve his mental health (hmmmm), and has even helped control his vitiligo, an autoimmune condition that causes patches of skin to lose color. Similarly, pop-academic Jordan Peterson has credited his all-beef and salt diet to alleviating his anxiety and depression—not to mention helping him lose 60 pounds.

But does the science beef up the claims? 

The Carnivore Diet is an extreme ketogenic diet that involves minimizing carb consumption in exchange for high-fat foods. Usually, our bodies use directly-available glucose from carbohydrates for energy. But when carbs are cut out of the diet in exchange for fats, there’s no immediately available glucose in the bloodstream, and so the body switches to using fat for fuel. In a process called “ketosis,” stored fat is broken down into molecules called ketone bodies. In ketosis, blood-sugar is more stable, there is less hunger, and energy levels are more consistent, Advocates of ketogenic dieting report reduced inflammation, increased energy and mental clarity.

Studies have demonstrated the efficacy of a ketogenic diet in weight loss, and even as a treatment option for epilepsy. Emerging research is even investigating the benefits of a ketogenic diet on other neurological disorders like Alzheimer's disease. That said, a ketogenic diet is restrictive, and certainly not for everyone. With such an elimination diet it can be more difficult to get the right nutrients. Furthermore, many people report experiencing “keto flu,” days of headaches, fatigue, and brain-fog. After all, forcing the body to use stored fat for energy, a ketogenic diet is effectively emulating a state of starvation.  

So what does this have to do with the Carnivore Diet? As mentioned, the Carnivore diet is an extremist cousin of the keto diet, and its advocates often back it with studies supporting keto diets. On a strictly Carnivore Diet, the body will enter a state of ketosis, in which it opts for fueling with stored fats because there's no glucose at-hand in the bloodstream–this may explain claims of dramatic weight-loss. But as we very well know, weight-loss is not always a useful metric for the healthiness of an eating routine. In fact, extreme weight-loss is often an indicator of the opposite. Beyond anecdotal evidence of miraculous effects of an all-meat diet, science does not back up the other claims of the Carnivore Diet, and most doctors recommend avoiding it. While a diet that induces ketosis may be beneficial for some people, changing the way the body burns fuel is not the only factor in a diet. Experts say that eating exclusively meat (unsurprisingly) misses the mark on several other important diet factors. 

First, the Carnivore diet is radically different from typical ketogenic diets because it calls for the complete elimination of carbohydrates–not just a reduction. With this complete elimination, as with other keto diets, there are increased risks of nutrient deficiencies. It’s extremely difficult to get enough of the necessary vitamins and nutrients from a strictly Carnivore diet. For even a chance of the Carnivore diet being remotely healthy, it can’t include just bacon and steak, it must also include a significant amount of nutrient-dense animal organs. Even then, experts worry about deficiencies, particularly fiber. The lack of fiber in the Carnivore Diet can cause severe constipation, which, besides being uncomfortable, can have serious complications. In short, the more restrictive a diet is, the greater the risks that you will be missing something, and the Carnivore diet is very restrictive.  

The Carnivore Diet is not just risky because it’s lacking important vitamins, nutrients, and fiber–it’s also possible to have too much of a good thing. Eating lots of meat can cause serious digestive issues, and eating lots of saturated fats, which are plentiful in the Carnivore diet, can elevate LDL cholesterol (the bad kind!) and increase risk of heart disease. The additional sodium that comes from a diet high in salty meats can cause high blood pressure and put extra pressure on your kidneys.  

Despite the risks of the Carnivore Diet, anecdotal evidence for it is in no short supply. Still, the long-term effects of an all-meat diet are vastly understudied, and the risks are high. For these reasons, medical professionals do not recommend trying the Carnivore diet, especially by anyone having a pre-existing condition like high blood-pressure or elevated cholesterol. Whether or not a diet is healthy for someone comes down to far more than just whether the body is burning fats or carbs. For some people, there may be nothing wrong with eating a high fat, low carb diet. But the vast majority of people will likely experience some problem if they stick to a meat only diet.


Elliot Durkee is a third-year honours undergraduate student studying Cognitive Science at McGill University.

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