Carnivore diet: weight loss game changer or unhealthy fad?

Have you ever wondered what it would be like to eat steak for every meal? If you’re a meat lover, the carnivore diet may sound like the perfect diet for you. But before starting on such an extreme diet, it’s important to understand what it entails, its potential benefits, and most importantly, its potential risks. Let’s take a look. 

A carnivore diet meal plan is simple—you only eat meat and other animal products. Red meats, ideally fattier cuts like ribeye steaks, are encouraged as the top food choices.

Here are some of the other allowed foods:

• Poultry

• Eggs

• Organs meats—liver, heart, kidneys, etc. 

• Bone marrow

• Fish

• Lard and tallow

• Butter

• Bone broth

• Processed meats—bacon, ham, etc. 

• Salt and pepper

Dairy products, yogurt, and cheese may be acceptable, but preferably those lower in lactose and sugar. 

The carnivore diet is pretty close to a zero-carb diet and is an extreme elimination diet. It removes all plant-based and non-animal foods.

Some examples of off-limits foods are:

• Fruits

• Vegetables

• Whole Grains and pasta

• Beans and legumes

• Condiments and sauces

• Nuts and seeds

Coffee and tea are one exception. Despite being created from plants, many carnivore dieters choose to keep these in their diet.

It’s possible to reach a lower body weight with any meal plan that cuts your caloric intake, and the carnivore diet is no exception to that. The limited menu options of this diet type might make it easier to avoid overeating.

The focus of the carnivore diet is fat and high protein. Both keep you feeling full for a long time and help reduce overeating, potentially leading to weight loss. 

People who follow the all-meat diet claim it’s easy to avoid mindlessly snacking and only eat when hungry.

The carnivore diet may put you into ketosis, but that isn’t the goal of the diet like it is in with the ketogenic diet. 

The keto diet focuses on increasing fatty foods with moderate protein intake and low carbohydrate intake. You need to pay close attention to your macros (protein, carbs, and fats) to optimize your fat to protein/carb ratio to keep you in ketosis.

Unlike the carnivore diet, the keto diet does promote eating low-carb green-leafy vegetables to encourage intake of fiber and micronutrients (vitamins and minerals).

The amount of ketones in your urine is monitored in the ketogenic diet to make sure you are in ketosis. In contrast, the carnivore diet requires no tracking for ketones or macros. 

It appears the carnivore diet is safe to follow for many people, at least for a short amount of time. Some people report following the carnivore diet for greater than a year without developing health problems.

Since around 2016, one of the biggest advocates for the carnivore diet has been Shawn Baker, an orthopedic surgeon. He has followed an all-meat eating style since 2015, showing at least he's been able to sustain the diet longer-term.

The information available to support the diet benefits is mostly anecdotal evidence. Any safety "evidence" comes from the claims of people following the diet and that there has been no research on long-term impacts on your body. 

There are many claims about the reported health benefits of following a carnivore meal plan. Here is a closer look at a few of these health claims. 

Fewer digestive symptoms

Fiber is a part of some fruits, vegetables, and grains that isn’t broken down during digestion. Instead, it helps to draw water to stool, adding bulk. Some of the bacteria in your gut break down fiber, causing bloating, gas, and other symptoms in some people. Some people are more sensitive to fiber. One study showed that reducing or cutting out fiber could help resolve constipation and other digestive symptoms in certain people (Ho, 2012). 

Better heart health

Some report that the carnivore diet helps to improve the ratio of good to bad cholesterol and reduces inflammation, leading to a healthier heart.

But research has found mixed results on these claims around heart disease risk and reduced inflammation. Some research shows no relationship between a high red meat diet and inflammation (Turner, 2018). 

One 2013 study found that a high-fat, low-carb diet helped improve blood lipid levels and systemic inflammation (Ruth, 2013). Other studies show that reducing saturated fats may improve cardiovascular disease (Hooper, 2020). So, the jury is out on this particular benefit. 

Increased testosterone

Testosterone levels naturally begin declining in men as they age. Carnivore dieters claim an all-meat diet keeps testosterone levels from dropping. 

One small study evaluated the effects of a very low-carbohydrate, high-fat diet on testosterone levels. It showed an increase in hormone levels for the young men following this diet plan, although the participants were only studied for about three months (Silva, 2014). 

Insulin sensitivity

Following a very low-carb diet may also help to increase insulin sensitivity (Silva, 2014). Your insulin sensitivity is how well your body responds to the hormone insulin, moving glucose from your bloodstream into cells to be used as energy. That means following the carnivore diet could help keep your blood sugar levels stable and reduce your risk of developing diabetes. 

While those benefits seem promising, there's poor testing on the health effects of the carnivore diet. We don't know all of the potential side effects of this diet. 

Increased digestive symptoms

People respond to fiber in different ways. While we saw above that some people do better when they reduce their fiber intake, others need more of it in their diet to alleviate symptoms. The bulking effect of fiber promotes regularity, helping relieve diarrhea and constipation. Plus, many healthy bacteria in your gut rely on plant-based fiber for food. Removing fiber from your diet could result in changes in bowel movements and other health effects. (Bae, 2014). 

Increased colon cancer risk

Plant-based diets are associated with reduced colon cancer risk (Orlich, 2015). By eliminating all plant foods, you could unintentionally increase your risk for diseases, like colon cancer, that antioxidants and other nutrients in plant foods help prevent. 

Advocates of the carnivore diet don't recommend any specific supplements. However, when following this diet, you likely won’t meet 100% of all recommended dietary allowances (RDA) for micronutrients. Some people choose to take a multivitamin to cover their bases to prevent nutrient deficiencies.

The carnivore diet plan may affect your metabolism in various ways, including changing your vitamin and mineral needs by lowering your daily needs for certain vitamins and micronutrients (O’Hearn, 2020). 

Organ meats are encouraged to prevent deficiencies since they are richer in many vitamins and minerals. 

Since people like Shawn Baker claim that they haven’t developed any signs of deficiencies, many advocates of the diet claim it is safe without supplements. Again, researchers need to study this more rigorously.

It’s difficult to know the long-term health effects of following a carnivore diet meal plan because there is little evidence-based research to support the claims or risks. 

The longest studies look at the health effects of the very low-carb, high-fat diet for six months at most. That isn't enough time to truly understand the benefits or risks of the carnivore diet over time. Many people who have followed the diet for greater than one year report their lab work is within healthy ranges. There hasn't been any research into these claims to accurately say how healthy eating an all-meat diet is.

This diet also ignores years of research about the beneficial health effects of how the bacteria living in our gut break down foods. High fiber foods promote a healthy balance of gut bacteria, including a type that creates short-chain fatty acids (SCFAs) that help reduce inflammation. In contrast, animal foods tend to create compounds that increase heart disease and inflammatory bowel disease risk (Tomova, 2019).  

The carnivore diet won’t be the right fit for everyone. If you choose to try this new meal plan, discuss this with your healthcare provider and monitor your blood work to see how it affects your health.

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

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Current version

April 28, 2021

Written by

Ashley Braun, RD, MPH

Fact checked by

Steve Silvestro, MD

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About the medical reviewer

Steve Silvestro, MD, Ro

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.