The carnivore diet, also known as the all meat diet, is a diet in which nothing but animal food sources are allowed.
The carnivore diet is founded on the theory that our ancestors survived on a diet which was composed mostly of meat — because gathering a lot of vegetables and fruit was not energy efficient for them.
Proponents of the carnivore diet claim that, for this reason, the human body has evolved to run optimally on a meat-based diet.
This controversial diet has recently become a popular trend.
Similar to — although more restrictive than — the ketogenic diet, the carnivore diet relies on eating only animal-sourced foods (including dairy). It also requires complete avoidance of carbohydrates, and ideally no nutritional supplements.
As a result, your body uses fats and proteins as energy sources.
What You Can Eat
Foods that you are allowed to eat on the carnivore diet include:
Fatty cuts of grass-fed red meat and steak are the primary ingredients of the carnivore diet. These meats are where you will obtain most of your calories.
Avoid lean cuts of meat to ensure you get enough calories to keep your energy level stable. Bacon and pork can also be used along with red meats.
So long as you are not lactose intolerant, you can eat full-fat milk, cheese, and butter.
Any type of fish is allowed in the carnivore die. Fattier fish such as halibut and salmon are preferred.
You can eat chicken and turkey, as well as organ meats.
Animal-derived fats such as tallow and lard are encouraged.
What to Avoid
You should avoid the following foods on the carnivore diet:
Avoid all forms of carbohydrates. That means no fruit, vegetables, legumes, bread, or sugar, including soda, chocolate, and candies.
Avoid all vitamins and nutritional supplements, when possible. This is based on the theory that all the minerals and nutrients your body needs can be found in the all-meat diet.
Transitioning to the Carnivore Diet
The best way to approach this diet is by making a gradual transition, especially if you’re used to eating a lot of foods high in carbohydrates.
You can increase your meat intake a little more each day. For the carnivore diet, you should eat fatty meat rather than lean cuts. Processed meat is also allowed.
If you start having cravings for other types of food, it is recommended that you eat more meat.
Proponents of the carnivore diet claim that cravings pass within a few days. If you find you’re losing a lot of water, you can drink fluids containing electrolytes.
Many people who turn to the carnivore diet plan start out with a ketogenic diet initially.
Adapting to the Carnivore Diet
Your body adapts to the carnivore diet plan in three main ways.
Because you are reducing your carbohydrate intake, your insulin level will drop. This drop triggers your kidneys to release sodium from your body.
It is possible to lose up to 10 lbs of water in the first few days after starting the carnivore diet.
As your body adapts, it will begin to convert glycogen to glucose and then switch to fatty acids.
Your body will transition from using sugar to fat for energy. If you have been eating a diet high in carbohydrate, you may feel cravings at this stage.
The two main hormones that have to adapt to the carnivore diet are cortisol and thyroid hormone. Initially, your T3 thyroid hormone may drop slightly, and your cortisol level may increase slightly.
Keep an eye on these markers to avoid any long term issues.
If you’re interested in trying out the carnivore diet for yourself, here are meal ideas to get you started.
Note: only begin this diet under the guidance of your healthcare provider or licensed nutrition.
- Bacon wrapped salmon
- Garlic baked chicken breast
- Ground beef patties
- Bone broth
- Roasted bone marrow
- Rib-eye steaks
- Marinated flank steak
- Grilled pork tenderloin
- Lemon Dover sole fillets
- Chicken bacon skewers
- Coconut lime skirt steak
Health Benefit Claims
According to orthopedic surgeon Dr. Shawn Baker — a major proponent of the carnivore diet plan and author of The Carnivore Diet — the all-meat diet may have the following benefits:
Improved Blood Sugar
A high- fat, low-carb diet, such as the carnivore diet may improve blood sugar. In a 2008 study, people suffering from type 2 diabetes and obesity who were given a ketogenic diet saw an improvement in their glycemic control. (Westman et al., 2008)
A 2017 paper published in Nature Communications suggests that a high-fat, low-carb diet may reduce inflammation in the brain. This theory is based on an animal study in which rats with brain inflammation were given a ketogenic diet. (Shen et al., 2017)
Improvement in Brain Health
A 2013 study published in Metabolism suggests that a zero-carb diet, such as the carnivore diet, may improve the brain’s neuroprotective properties. This, in turn, could improve mental clarity and reduce the effects of oxidative stress on brain health. (LaManna et al., 2009)
Increase in Testosterone
In a 1996 study published in the American Journal of Nutrition, 43 men were given either a high-fat, low-fiber diet or a low-fat, high-fiber for ten weeks. The results showed that the men who adopted a high-fat, a low-fiber diet had a 13% increase in testosterone compared to the other group. (Dorgan et al., 1996)
While the carnivore diet does show evidence of faster weight loss compared to low-carb or low-fat diets, this difference in weight loss levels out over time.
The Theory Behind Diet
When you restrict or remove carbohydrates from your diet, your body’s need for certain nutrients decreases.
Certain vitamins required for the metabolism of carbohydrates, for example, are not as essential in your body.
A 2014 study in the Journal of Clinical Medicine examined the effects of vitamin A on macronutrient metabolism.
The results showed that on a carbohydrate-free diet, vitamin A is no longer necessary for metabolic regulation. (Chen et al., 2014)
When you adopt a low-carbohydrate, high-fat diet — such as the carnivore diet — your body seeks other sources of energy. Eventually, your body will enter a state of ketosis. Ketosis is a natural metabolic state. Its name derives from the term “ketones,” which refers to small molecules of fuel within the body.
Ketones are produced from the fat in your diet. Your body uses these ketones for energy when glucose is in short supply.
You can promote the production of ketones in your body by restricting your carbohydrate intake. Your liver will convert fat to ketones, which will then enter your bloodstream. From there these ketones are used as energy — instead of glucose.
There is a significant problem with the carnivore diet. The carnivore diet is not a ketogenic diet. It includes too much protein to trigger ketosis in the body. The body disposes of excess protein through gluconeogenesis. In this process, the liver turns excess protein into glucose, which defeats the whole purpose of the carnivore diet. (Schutz 2011)
Is It Worthwhile?
While there are many advocates of the carnivore diet — some in the medical profession — there are many problems with the diet, casting doubt on its worthiness.
Your body needs 13 essential vitamins to stay healthy. Unfortunately, you cannot get all of them from the carnivore diet. Essential vitamins such as vitamin C, vitamin E, and folate are found mainly in fruit, vegetables, and legumes.
Furthermore, if you have a vitamin E deficiency, your body will be unable to use vitamin K properly with the carnivore diet. Vitamin K is essential for blood clotting and the synthesis of protein.
The next issue with the carnivore diet is the lack of fiber. Meat does not contain fiber. But fiber is essential for a healthy diet. Fiber helps your body’s gastrointestinal system maintain the right balance of beneficial bacteria, which affects everything from your digestive process and your mood, to your immune system.
When you eat meat and processed meat, you can increase your risk of colon cancer by between 20-30%. (Aykan, 2015)
According to the World Health Organization, processed meats such as bacon, frankfurters, salami, and ham, are Group 1 carcinogens, meaning there is strong evidence supporting their link to cancer. (Cancer Council Meat and Cancer, n.d.)
Red meat, such as beef, pork, and lamb, when cooked at temperatures exceeding 300 degrees Fahrenheit, can produce carcinogenic chemicals. (NIH Cancer Causes and Prevention, 2017)
To stay healthy, you need to maintain a higher level of HDL (good cholesterol) and a lower level of LDL (bad cholesterol) along with low triglyceride levels. Eating fatty red meats increases LDL while lowering HDL. It also increases triglyceride levels. This may increase your risk of heart disease, metabolic syndrome, and obesity.
The main reason why people lose weight initially, on the carnivore diet plan, is that they likely consume fewer calories.
However, while the carnivore diet may initially result in weight loss, over time, a diet high in fats may cause weight gain. Thyroid function may also slow down as a protective mechanism, lowering the metabolic rate.
Liver and Kidneys
Another problem with the carnivore diet is that it places a heavy burden on the kidneys and the liver. When you eat a high-protein diet, your body metabolizes nitrogen molecules and converts them into ammonia. The liver converts ammonia into urea, which passes through the kidneys and is eliminated as urine.
To break down proteins, this process (known as the urea cycle) uses genetically coded enzymes. This means that people can respond differently to a diet plan that is high in protein based on their genetic make-up. (Harvard Health Publishing, 2007)
Urinary Tract Infection
E. coli – the pathogenic bacteria responsible for urinary tract infections (UTI) – thrives in acidic urine. The carnivore diet may create an acidic environment in both the body and the urine. In women, this can increase the risk of a UTI, while in men it can increase the risk of prostatitis.
Similarly, an acidic environment in the body’s tissues can also increase the risk of osteoporosis in some people.
Although some studies have shown that a diet slightly higher in protein can benefit bone density, (Cao et al., 2010) such studies only examine the effect of protein on bone density with regards to a balanced diet, not an all-meat diet.
Is the Carnivore Diet Right for You?
Many individual factors contribute to how a diet may affect you. The carnivore diet, like any extreme diet plan, may cause health problems. The most effective way to stay healthy and lose weight is to maintain a balanced diet and exercise regularly.
If you have food sensitivities, you might want to check out an elimination diet plan such as the FODMAP diet.