Only eating meat for the rest of your life: for some, it might sound too good to be true. Is it possible to be healthy eating nothing but steak? What can the carnivorous cultures of the world teach us? Read on to learn more about the carnivore diet.
What Is the Carnivore Diet?
The carnivore diet, also called zero carb, is exactly what it sounds like: its adherents eat only meat. Some people are more strict than others about what counts as meat; animal products like milk, cheese, and eggs are a topic of debate. Some people salt their food, while others claim not to need it.
People are most commonly following a carnivore diet to alleviate autoimmune or inflammatory issues.
Critics of the carnivore diet say that it destroys the intestines and can’t provide all the nutrients the human body requires. Meanwhile, some proponents of the carnivore diet may point to people like the Maasai and Inuit, who eat traditional diets of almost exclusively meat. But are these people true carnivores? [1, 2]
Generally speaking, the colder the environment, the less plant life grows there. This means that people who traditionally live in very cold climates tend to eat more meat and less plant matter. The Chukotka people of Siberia and the Inuit and Eeyouch (northern Cree) of Canada are great examples of such cultures [3, 4, 5].
However, none of these cultures completely cut plants out of their diets; in fact, they would go to great lengths to gather and eat fruits, roots, and medicinal herbs during the warmer seasons [3, 4, 5].
Consider the Eeyouch of Eeyou Istchee, a bitterly cold territory in northern Quebec. The vast majority of a traditional Eeyouch diet is made up of wild game like moose and caribou, fowl like goose, and fish. However, during the summer months, they gather huge quantities of wild blueberries and Labrador tea. All year round, they make tea with white spruce needles and gather a variety of medicinal plants and mosses [5, 6, 7].
Even the Maasai people of Kenya and Tanzania – whose famously carnivorous diet is made almost entirely of cow’s blood, meat, milk, and honey – eat herbs, roots, and tree bark as part of traditional medicine [8, 9].
Snapshot of the Carnivore Diet
- Eliminates potential irritants such as gluten & lectins
- Decreases inflammation in people who are sensitive to various plant-based irritants
- High energy and high protein
- Devoid of sugar, flours, refined, processed and junk foods
- Likely causes weight loss based on anecdotes and also since it’s hard to overeat given the food limitations
- High risk of nutrient deficiencies
- Doesn’t contain healthy compounds such as polyphenols & fiber
- Might not be ideal for longevity if not combined with fasting (high protein diets activate mTOR and IGF-1)
- May result in lower brain serotonin (carbohydrates increase serotonin in the brain) [10, 11, 12].
- Increases oxidative stress
- May cause gut microbiome issues
- Large carbon footprint
Carnivore Diet Benefits
So, what’s the deal? Why do this? Unfortunately, the health effects of the carnivore diet are poorly studied, but its proponents have a few arguments.
One such line of reasoning is evolutionary. Some people claim that humans are “meant” to eat meat because when our ancestors started eating meat, the extra energy and protein helped them get bigger, faster, and smarter very quickly. This much is true: the transition from a plant–only diet to an omnivorous diet coincided with a massive expansion in brain size .
Most people who eat a carnivore diet are likely to say that they eat this way to avoid the “toxins” or antinutrients in plant matter. They point to compounds like gluten, oxalates, lectins, histamine, and other potentially inflammatory compounds found in plant-based foods, which may cause serious illness in people who are sensitive to them [14, 15, 16].
For sensitive people, avoiding these foods may alleviate inflammation or autoimmune issues.
Joe Cohen, the founder of SelfHacked, actually started this website because he had unresolved inflammatory issues that he was trying to fix. His breakthrough came when he realized that most of his issues were from various components in plant-based foods.
But let’s put this diet in perspective: it’s not a solution for the masses. Rather, the carnivore diet should be regarded as a therapy for specific people.
As such, this post is not intended to discourage the diet. The point of this post is to make people aware of the potential deficiencies so that they can supplement properly and avoid the negatives.
Deficiencies From the Carnivore Diet
The glaring drawback of the carnivore diet is what’s missing from the meat.
The common commercial cuts of beef, pork, and chicken do not contain all of the vitamins, minerals, and compounds required for human health… and over enough time, these deficiencies can be extremely dangerous.
That being said, most of the nutrients listed here can be found in organ meats: liver, kidney, sweetbreads, lungs, brain, and so on. Thus, the key to these deficiencies may be that many people eating a carnivore diet do not eat enough organs [17, 18].
If you are still getting less than the recommended levels, you should take supplements. Even if you’re getting sufficient amounts, it’s important to realize that “just enough” is often not ideal. Some people may need more than the recommended nutrient intakes for optimal health .
Note: In the meal scenarios below, we don’t count the nutrients that you would get from Himalayan salt if you were consuming it. Despite claims that Himalayan salt contains a wide variety of minerals, these are only present in small amounts that would not move the needle for any nutrient.
1) Vitamin A
The daily recommended intake of vitamin A (as retinol) is 700 – 900 mcg per day. 3 ounces of beef liver provides many times that. Liver, in general, is a great source of preformed (active) vitamin A or retinol .
Grass-fed beef contains significantly more beta-carotene (a compound that is converted to vitamin A in the human body) than grain-fed beef. The highest-quality grass-fed steak may have as much as 740 mcg of beta-carotene per kilogram of meat, while grass-fed beef liver may contain 10 times that amount! [21, 22, 23]
Overall, beef liver is still richer in both active vitamin A and carotenoids than steak: the average beef liver has 1398 mcg of retinol per ounce, whereas steak will contain anywhere from about 0 – 15% that amount [21, 22, 24, 25, 23].
The following meal scenarios assume that a person eats 2 pounds of meat per day and uses the daily recommended intake for men (which is a bit higher than for women):
- All Beef (not grass–fed)*: About 73 mcg as beta-carotene (retinol may be close to 0). Beef briskets are higher in retinol than beef steak. If eating only briskets, deficient in vitamin A by about 75%. If eating only steak, deficient in vitamin A by over 96% [21, 23, 28].
- All Beef (grass-fed)*: About 409 mcg as beta carotene. The retinol content can widely vary. If the retinol content is low, possibly deficient in vitamin A by about 27% [21, 23].
- Half grass–fed beef* & half chicken (thigh): About 206 mcg. Deficient in vitamin A by 77% .
- ⅔ lb beef, ⅔ lb chicken (thigh), ⅔ lb salmon: 518 mcg. Deficient in vitamin A by 43% .
- 9 oz beef*, 9 oz chicken (thigh), 9 oz salmon, 5 oz chicken liver: 5,210 mcg. More than enough vitamin A [30, 31].
*“All beef” and “beef” refers to muscle meat, typically steak. Unlike steak, beef liver is exceptionally high in vitamin A. By adding just an ounce of beef liver a day, you would get more than vitamin A you need.
Please note: the maximum recommended intake of vitamin A is 3000 mcg per day. To reduce the risk of long-term vitamin A toxicity, consider eating liver on some days and replacing it with other organ meats, mollusks, and fish on others [32, 33].
Pregnant women should be especially careful not to consume too much vitamin A, as high levels have been linked to birth defects. In general, it’s safer to avoid liver altogether (and especially beef or pork liver) during pregnancy .
2-3) B Vitamins
Biotin (vitamin B7) and folate (vitamin B9) are essential to energy metabolism, DNA protection, and cell division. Biotin deficiency starts with hair loss and red rashes and progresses to neurological disorders; folate deficiency causes a type of anemia with large, deformed red blood cells [34, 35].
These vitamins aren’t the most difficult to get from meat sources, but organs are richer than muscle meat cuts. Beef liver is very rich in both biotin and folate; 3 ounces of beef liver delivers all the biotin and about half the folate you need in a day [34, 35].
Other rich sources of biotin include eggs and salmon. Most liver contains plenty of folate, though fowl (goose, duck, turkey, and chicken liver) are the richest. A single goose liver contains almost twice the daily recommended intake of folate [34, 35, 36].
The MTHFR genetic variants, which about 40% of people have, can up your dietary folate requirements.
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the daily recommended intake for non-pregnant adults:
- All beef (not grass–fed): 40 mcg biotin & 127 mcg folate. Sufficient biotin, deficient in folate by 68% [37, 38].
- All beef (grass–fed): We couldn’t find a study that determined the biotin and folate content of grass-fed beef. Given the pattern of other vitamins, grass-fed beef is likely to be richer than grain-fed beef in both biotin and folate, but actual quantities are unknown, and deficiency is likely.
- Half grass–fed beef & half chicken (thigh): 26 mcg biotin & 77 mcg folate. Deficient in biotin by 13%, deficient in folate by 81% .
- ⅔ lb beef, ⅔ lb chicken (thigh), ⅔ lb salmon: 35 mcg biotin & 158 mcg folate. Sufficient biotin, deficient in folate by 60% [37, 30].
- 9 oz beef, 9 oz chicken (thigh), 9 oz salmon, 5 oz chicken liver: 294 mcg of biotin & 964 mcg of folate. More than enough of both [30, 31].
“All beef” and “beef” refers to muscle meat such as steak. Beef liver, on the other hand, is high in folate – even more so than chicken liver. In the last scenario, you could switch chicken liver with beef liver. About 5 oz of beef liver will also meet your daily folate requirements .
4) Vitamin C
Vitamin C is essential in the human diet because we cannot make this compound on our own. We need it to make some hormones and to lay down collagen, a stretchy protein that helps us heal wounds. Vitamin C is very easy to get from fruits and vegetables; it is extremely difficult to source from meat [40, 41].
The recommended daily intake of vitamin C for an adult is 75 – 90 mg. Very high quality, pasture-raised South American beef can contain as much as 2.5 mg of vitamin C per 100 g of meat, but this is the exception, not the rule. Meat must be of high quality, grass fed, fresh, and either raw or lightly cooked to maximize vitamin C content [41, 22, 42].
In order to get enough vitamin C from a strict carnivore diet, you would need to eat organs like spleen, thymus, and lung (raw or lightly cooked!). 100 g of beef spleen contains, on average, 50 mg of vitamin C [41, 43, 44, 45].
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the daily recommended intake for men:
- All beef (not grass–fed): 0 mg. Deficient in vitamin C by 100% .
- All beef (grass–fed): as much as 23 mg. Deficient in vitamin C by at least 75% .
- Half grass–fed beef & half chicken: as much as 11.5 mg. Deficient in vitamin C by 87% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: 20 mg. Deficient in vitamin C by 78% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 42 mg. Deficient in vitamin C by 53% [30, 31].
If you add 100 g (about 3.5 oz) of beef spleen to the last scenario, you could get 86.6 mg of vitamin C, which is right on the edge of enough. If you eat more liver, you can nudge vitamin C up, but then you may risk getting too much vitamin A and associated bone, nerve, and liver damage over time .
Hence, vitamin C is a difficult essential nutrient to get in a carnivore diet.
When we are eating enough vitamin C daily, the human body stores about 1,500 mg of it at a time. If that storage level gets below about 350 mg (after 8 to 12 weeks of poor intake), symptoms of scurvy start to appear: irritability, anorexia, tooth loss, poor wound healing, brittle bones, and more .
It is very important to get enough vitamin C in your diet. If you don’t eat spleen, thymus, and lung, consider supplementing to reach your daily recommended intake. There have been multiple cases of people developing scurvy as a result of eating only meat [2, 42].
Your risk of dying from all causes goes down if you have higher blood levels of vitamin C, which is influenced by dietary vitamin C [47, 48, 49]. So even if you don’t get scurvy, higher intakes of vitamin C (or at least the foods that contain vitamin C) are beneficial.
Note: We have not seen case reports of people getting scurvy on a carnivore diet, but this doesn’t mean their vitamin C levels are optimal.
5) Vitamin E
Vitamin E is a fat-soluble antioxidant that protects tissues while fat is burned for energy. Severe deficiency is rare, but low intakes of vitamin E can lead to high oxidative stress and tissue damage .
The recommended daily intake of vitamin E is 15 mg, and it is difficult to source from meat. 100 g of fish eggs contain about 7 mg of vitamin E. Other good sources include snails and salmon [50, 51, 52, 53].
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the daily recommended intake for adults:
- All beef (not grass–fed): 2.6 mg. Deficient in vitamin E by 82% .
- All beef (grass–fed): about 3.4 mg. Deficient in vitamin E by 78% .
- Half grass–fed beef & half chicken: 3.4 mg. Deficient in vitamin E by 78% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: Up to 13 mg. Deficient by 13% or more .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 12 mg. Deficient in vitamin E by 20% [30, 31].
If you add 100 g (about 3.5 oz) of fish eggs (roe) to the last scenario, you could get 19 mg of vitamin E. Adding more salmon, olive oil or supplementing with vitamin E would also help. However, as you can see, it’s very difficult to get enough vitamin E on a strict carnivore diet.
6) Vitamin K
Vitamin K is actually a family of related compounds important for blood clotting and bone metabolism. Deficiency may cause haemorrhage, excessive bleeding, and osteoporosis. Leafy green vegetables are very high in vitamin K (K1); this vitamin is more difficult to source from meat, though pork and chicken contain relatively high levels of vitamin K2 [55, 56, 57].
The daily recommended intake of vitamin K is 90 – 120 mcg. 100 g of canned tuna contains up to 44 mcg of vitamin K, but may also contain vegetable oils. Some cuts of high–quality, lean beef may contain 17.5 mcg per 100 g of meat [55, 58, 59].
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the daily recommended intake for men:
- All beef (not grass–fed): About 74 mcg. Deficient in vitamin K by 39% 
- All beef (grass-fed): 159 mcg or more. More than enough vitamin K .
- Half grass–fed beef & half chicken: About 182 mcg. More than enough vitamin K .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: About 121 mcg. Just enough vitamin K .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: About 102 mcg. Deficient in vitamin K by 15% [30, 31].
The importance of high-quality, grass-fed beef is especially clear here. You could add 23 mcg of vitamin K by eating 100 g (3.5 oz) of abalone, a type of edible sea snail .
If you include dairy in your diet, whole milk and cheese are rich in menaquinones, a form of vitamin K2. 100 g (3.5 oz) of soft cheese (such as Brie or camembert) contains about 506 mcg of menaquinones .
Most people eating an omnivorous diet don’t have to worry about boron deficiency because this micronutrient is plentiful in fruits and nuts. You may not be able to source boron from meat, fish, or shellfish [65, 64, 66].
There is no daily recommended intake of boron; the recommended upper limit is 20 mg per day. Milk and coffee, together, account for about 12% of the total boron consumed by Americans. Strict adherents to the carnivore diet may need to supplement with boron [67, 66].
The following meal scenarios assume that a person eats about 2 pounds of meat per day and compare to the minimum “normal” intake of 0.8 mg per day :
- All beef (not grass–fed): less than 0.015 mg. Deficient in boron by at least 98% .
- All beef (grass–fed): Unknown. The difference has not been studied; however, other minerals vary depending on the content of the grass .
- Half grass–fed beef & half chicken: less than 0.015 mg. Deficient in boron by at least 98% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: less than 0.015 mg. Deficient in boron by at least 98% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: less than 0.015 mg. Deficient in boron by at least 98% .
Boron is a poorly-studied micronutrient. Future studies may emerge which find different forms of boron (borates) in animal tissues. For the time being, however, you may wish to consider supplementation.
If you don’t supplement, the best solution for getting enough boron on a carnivore diet is to consume bones.
When a person’s diet is deficient in calcium, the body “steals” calcium from the bones, leading to osteoporosis. Other symptoms of calcium deficiency include muscle cramps, irregular heartbeat, and numbness or tingling in the fingers .
The most important source of calcium in the Western diet is dairy. If you drink milk or eat dairy products like yogurt, you won’t need to worry about calcium. However, strict adherents to the carnivore diet will need to think about where they get their calcium .
The daily recommended intake of calcium is 1,000 – 1,200 mg for an adult. Canned fish that includes bones (such as sardines) contains up to 455 mg per 100 g. A similar amount of high–quality beef tripe contains about 158 mg of calcium [71, 72, 73, 74].
You may be able to get some calcium from high-quality unrefined salt such as Himalayan rock salt (pink salt). However, rock salt is at most about 1.7% calcium, so it should not be considered a sufficient source .
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the daily recommended intake for men:
- All beef (not grass–fed): Up to 200 mg. Deficient in calcium by 83% .
- All beef (grass–fed): About 1.3 times the content of grain-fed beef, which could be up to 260 mg. Deficient in calcium by at least 78% .
- Half grass–fed beef & half chicken: Up to 162 mg. Deficient in calcium by 87% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: Up to 193 mg. Deficient in calcium by 84% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: Up to 174 mg. Deficient in calcium by 86% [30, 31].
Eating high-quality beef tripe or keeping the bones in your salmon can help you increase your calcium intake. Milk has a lot of calcium, but it can cause health issues, especially in people who are drawn to a carnivore diet [77, 74, 78].
If you don’t supplement, the best solution for getting enough calcium on a carnivore diet is to consume bones.
Potassium is an essential nutrient that regulates fluid balance in cells and maintains healthy bone tissue and blood pressure. Deficiency can cause increased blood pressure, kidney stones, constipation, muscle weakness, large quantities of watery urine, and irregular heartbeat .
Blood pressure responds to both potassium and sodium; without enough potassium, blood pressure will be more sensitive to sodium and will fluctuate more depending on sodium intake .
Fruits and vegetables are rich in potassium; meat is not a great source. Some of the best sources of potassium for a carnivore include mollusks (especially octopus, with 630 mg of potassium in 100 g) and salmon, but even these are low compared to plant foods [79, 81, 82].
Carnivores may also consider using low-sodium, high-potassium salt substitutes like LoSalt. These products replace a portion of the sodium chloride (NaCl) of table salt with potassium chloride (KCl) .
The following meal scenarios assume that a person eats about 2 pounds of meat per day and use the USDA daily recommended intake:
- All beef (not grass–fed): Up to 3,372 mg. Deficient by 28% .
- All beef (grass–fed): Very slightly (about 4%) higher than grain-fed, or up to 3,527 mg. Deficient by 25% .
- Half grass–fed beef & half chicken: 2,686 mg. Deficient by 43% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: 3,318 mg. Deficient by 29% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 3,125 mg. Deficient by 34% [30, 31].
If you choose to add milk, cheese, or eggs to your diet, these will help increase your potassium intake. Mollusks are relatively rich: a 3-ounce “baby” octopus contains about 536 mg of potassium [84, 81].
It may still be very difficult to get enough of this nutrient in a carnivore diet and you may wish to supplement.
The daily recommended intake of copper is 900 mcg for an adult. Beef and veal liver are extremely rich in copper, with about 15 mg of copper per 100 g of liver. Other rich meat sources of copper include mollusks and sweetbreads (thymus and pancreas) [85, 86, 87, 88, 89].
Muscle meats alone may not have enough copper, unless you’re eating only beef. Add a bit of liver to make sure you reach your daily recommended intake.
On the other hand, it is possible to eat too much copper. Very high doses of copper (over 30 mg per day) may cause liver and nerve damage over a long period of time .
- All beef (not grass–fed): Up to 973 mcg. Sufficient intake of copper .
- All beef (grass–fed): About 636 mcg, depending heavily on the mineral content of the grass. Deficient in copper by 29% . Grains contain a lot of copper, hence why grass-fed might have less.
- Half grass–fed beef & half chicken: 564 mcg. Deficient in copper by 37% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: 533 mcg. Deficient in copper by 41% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 1,145 mcg. Sufficient intake of copper [30, 31].
Magnesium is important for energy metabolism, mood, protein building, bone development, and DNA production. Deficiency is rare because the kidneys are very good at holding on to magnesium if we’re not getting enough in our diets; however, over time, low magnesium intake can lead to nausea, vomiting, fatigue, numbness, muscle cramps, seizures, and personality changes .
The daily recommended intake of magnesium is 320-420 mg. It is most abundant in nuts and beans and very difficult to source from meat. Good sources of magnesium include fish eggs, mollusks (such as snails), cod, and salmon [92, 93, 52, 94, 95].
Bone broth can also be a good source of magnesium, but only if it’s properly prepared. If you make your own bone broth at home, be sure to cook it for at least twelve hours: it can then contain about 120 mg of magnesium per liter .
- All beef (not grass–fed): As high as 227 mg. Deficient in magnesium by 46% .
- All beef (grass–fed): As high as 227 mg, depending on the mineral content of the grass. Deficient in magnesium by 46% [76, 91].
- Half grass–fed beef & half chicken: 195 mg. Deficient in magnesium by 54% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: about 378 mg. Deficient in magnesium by 10% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 346 mg. Deficient in magnesium by 18% [30, 31].
Magnesium is one of those nutrients where it is often the case that the more you take the better, as long as you don’t get diarrhea. You may want to get up to 600 mg a day from your food and supplements. In most cases, though, we don’t recommend going above 350 mg per day with supplements. If you are on a carnivore diet, we at SelfHacked recommend that you supplement in moderation [97, 98].
Manganese is important for bone formation and for the metabolism of fats, carbs, and proteins. Deficiency can cause slow growth (during childhood and adolescence) and poor bone health. Manganese may interact with vitamin K metabolism as well; deficiency in manganese may cause symptoms similar to vitamin K deficiency .
The daily recommended intake of manganese is 1.8 – 2.3 mg for adults. 100 g of blue mussels contain 3 – 6 mg of manganese. Other rich sources include beef tripe (6 mg per 100 g), bass (1.14 mg per 100 g), and trout (1.09 mg per 100 g) [99, 100, 101, 74, 102, 103].
- All beef (not grass–fed): 0.13 mg. Deficient in manganese by 94% .
- All beef (grass–fed): as low as 0.08 mg and as high as 0.18 mg, depending on the mineral content of the grass. Deficient in manganese by 92-99% 
- Half grass–fed beef & half chicken: 0.15 mg. Deficient in manganese by 93% .
- ⅔ lb beef, ⅔ lb chicken, ⅔ lb salmon: 0.13 mg. Deficient in manganese by 94% .
- 9 oz beef, 9 oz chicken, 9 oz salmon, 5 oz chicken liver: 0.47 mg. Deficient in manganese by 80% [30, 31].
Most meats contain very little manganese, and you will almost certainly have to go off the beaten path to make sure you get enough. As mentioned above, blue mussels, beef tripe, bass, and trout are rich in manganese. Substituting some beef for grass–fed bison (11.5 mg in 3.5 oz) will also take care of the requirement .
It’s very hard to get these foods on a steady basis, so it’s likely that if you are on a carnivore diet, you will need to supplement with manganese.
If you don’t supplement, the best solution for getting enough manganese on a carnivore diet is to consume shellfish.
Lithium is a trace mineral that isn’t essential, although, at low concentrations, it has a lot of benefits.
The primary sources of lithium are grains and vegetables i.e. plant-based sources .
Healthy Plant Components
The best antioxidants are plant polyphenols like flavonoids, lignans, and stilbenes. Since the turn of the century, these compounds have been the subject of intense research. Some scientists consider them essential to human health [107, 108, 109, 110].
Although not essential, plant polyphenols help protect the body against cancer, heart disease, nerve damage, and more. People who get less of these compounds in their diet are at greater risk for age-related diseases .
This antimicrobial activity is even more important on a carnivore diet because of the bad bacteria that grows on meats, such as E. coli.
However, some strict carnivores may think of these compounds as the kind of “plant toxins” that they are trying to avoid. Nevertheless, a growing body of research suggests that they are necessary for optimal human health.
Joe’s experience to polyphenols on their own didn’t involve any negative reaction. As a general rule, he believes that polyphenols should be supplemented with on a carnivore diet, based on his personal and client experience.
A healthy digestive system contains dozens of species of beneficial bacteria. These bacteria, collectively called the gut flora or gut microbiota, help digest our food and produce bioactive compounds that we absorb through the intestinal wall. The composition of the gut flora can change very quickly with changes in diet .
Many nutritionists and doctors consider fiber to be essential for healthy human gut flora. When we don’t eat enough fiber, the gut flora eats away at the mucus of the intestinal wall, which makes us more likely to get sick. Meat contains almost no fiber at all, so this harmful change is likely on the carnivore diet [1, 113].
The daily recommended intake of fiber is around 25 g per day for women and 38 g per day for men. For a more personalized approach, the National Academy of Medicine (formerly the Institute of Medicine) recommends 14 g of fiber for every 1,000 calories consumed .
Myo-inositol is a very healthy compound found in a lot of foods. The greatest amounts of myo-inositol are present in fruits, beans, grains, and nuts .
17) Oxidative Stress
Eating a lot of meat has been linked to heart disease and cancer, likely because cooking meat releases substances (heterocyclic amines) that increase oxidative stress .
These toxic substances build up when meat is cooked at high temperatures (at 150 – 200 °C), such as by barbecuing, grilling and pan-frying. It would be best to limit charred meats. Focus on cooking methods that don’t brown the meat, such as slow-cooking .
Optimal levels of GGT are below 15. Joe, with his meat-based diet, has low GGT (14), but that’s probably because he supplements with plenty of healthy compounds. So anecdotally, you can have low levels of oxidative stress while consuming a meat-based diet, but it needs to be done right.
In summary, people who eat a carnivore diet should aim to reduce oxidative stress. One strategy is to up antioxidant intake. An additional strategy is to eat fattier meat and include a lot of olive oil with every meal, since ketogenic diets improve mitochondrial health and lower oxidative stress [119, 120].
Extra Requirements for Antioxidants
Sun exposure is quite helpful for many people autoimmune and inflammatory problems .
If you ingest a high enough dosage of vitamin E, it can protect you from UVB rays .
Whenever people in history were exposed to more sun, they also ate more fruits and vegetables. In northern latitudes in the winter, people get less sun and also eat less fruits and vegetables. If you are eating a carnivore diet in a sunny area, that is likely not a good combination if you don’t supplement with antioxidants and polyphenols.
Now we at SelfHacked think that there are a lot of benefits to the sun, and we encourage moderate sun exposure. However, we also realize that people need to make sure they’re getting a good amount of antioxidants and polyphenols in their diet as protection from skin cancer.
Unfortunately, plant-based foods are many times richer in antioxidants than animal–based foods, even accounting for the vitamin E content of fish like salmon .
To prevent oxidative stress to your tissues, consider using supplements .
Carnivore Diet Supplements
- Multivitamin (must contain: vitamin A, B9, Biotin, C, E, K, boron)
- Magnesium and Calcium
- Lithium Orotate
- Curcumin (a polyphenol)
- Resistant starch (soluble fiber)
- Psyllium husk (insoluble fiber)
Arguments from Carnivores
Advocates insist that if you follow a carnivore diet you’ll be perfectly healthy. What’s more, they say you’ll have lower nutrient requirements, that you can get all the vitamin C you need from meat, and that nutrients are more bioavailable in meat anyway. Some claim this diet cures a long list of diseases. And carnivores are certain that humans are actually meant to eat only meat, while plant antinutrients will wreak havoc in the body.
Carnivore diet critics are on the other end of the spectrum. For them, this diet is downright dangerous and nobody in their right mind would follow it.
What’s the truth? We took a deep dive into the science to address all the common arguments from carnivores in this post.
Limitations and Caveats
The biggest limitation of any discussion of a carnivorous diet is the lack of research on its effect on the human body. All of the studies on an animal-based diet were either very short (a few days), case studies of Antarctic explorers or victims of scurvy, or anthropological reviews of cultural practices (which always involve at least some plants).
Studies that last a few days can only tell you what the carnivore does over the course of a few days. In the longer term, poor nutrition may cause thyroid and hormonal problems and nutrient deficiencies, but these are not well documented in the specific case of the carnivore diet.
Proponents of the carnivore diet claim that the human body’s nutritional requirements are different after several months of eating only meat, but there is no research to back them up.
Some case studies of Antarctic explorers suggest that human bodies can adapt to eating only (freshly killed, sometimes raw) meat over a long period of time. Other case studies of people with scurvy suggest that a truly healthy carnivore diet is almost impossible for the modern, city-dwelling person: vitamin C and other nutrients are missing from commercial meat and many organs are difficult to find and buy.
A lot of people make a lot of claims about the carnivore diet. The landscape may be difficult to navigate; always check people’s claims against their sources to make sure you have the best information available.
People who eat carnivore or zero carb diets have formed active, engaged communities online. Lots of user experiences, anecdotes, and recommendations are available for anyone to read.
Many people who eat a carnivore diet say that they have more energy and mental clarity. This was Joe’s experience.
Some people claim that the carnivore diet improved or eliminated their irritable bowel symptoms. Beware, however: some people also describe a difficult transition period of nausea, vomiting, and diarrhea.
Other people have horror stories. Some developed scurvy and their teeth and hair started falling out. Others fell into depression and suffered powerful cravings for fruits, vegetables, and sugars. Thyroid problems, high cholesterol, and menstrual irregularities sometimes emerge after several months on the carnivore diet.
Many people who eat a carnivore diet are not extremely strict. They say that they eat a ketogenic diet or low carb high fat (LCHF) diet in social settings and eat only meat in the comfort of their home.
Strict adherents to the diet describe nausea, vomiting, diarrhea, and severe fatigue after eating a piece of bread or fruit.
Genetics: The Carnivore Diet Gene
CNR1 sounds like carnivore, but there’s no relation. It’s actually the Cannabinoid Receptor 1. If you have a T allele, then it means that you want to try out a carnivore diet. If you have 2 T alleles, as Joe and Mikhaila have, then you DEFINITELY want to try out a carnivore diet. Joe has found with his clients that those with 2 alleles (around 3 percent of the population) always had food sensitivities as a root of their problem.
|SNPs||Problematic Allele or Genotype|
|Cannabinoid Receptor 1 (CNR1)||rs1049353||T|
If you negatively react to plant-based substances, you are more likely to do well on a carnivore diet. To understand how your genetics can impact your predisposition, readthis post on genes, symptoms, and blood tests that may indicate your sensitivity to plant substances.
Joe developed the SelfHacked Lectin Avoidance Diet to help himself and clients with chronic inflammation and autoimmunity figure out which foods they are reacting to. In a nutshell, it is very similar to the carnivore diet but with additional well-researched components. These are added to prevent nutrient deficiencies and reduce the health risks of consuming a high-protein diet.
Rather than going through a trademarked or one-size-fits-all approach, it is best to eat a diet that is as diverse as possible. Therefore, the SelfHacked Lectin Avoidance Diet is also an elimination-reintroduction protocol. You remove most common food sensitivities until your symptoms subside, then bring them back one at a time to determine what you react to.
At the end of the diet, you should be able to eat diverse foods without experiencing inflammatory symptoms. Once your inflammation is well-managed, you may even be able to occasionally consume some foods you are sensitive to.
Here are the resources we recommend diving into for more detailed information:
- DNA Vitamin Report and Mineral Report – lets you know which vitamins and minerals you may need more of based on your genetics. We are all unique.
- The SelfHacked Elimination Diet course, which both breaks down the science and gives you practical step-by-step instructions. The goal is to help you pinpoint your food sensitivities to plant substances and ways to overcome them.
- The All About Inflammation course provides background info and science of inflammation in a layperson-friendly way
- SelfDecode can help you gain valuable insights from your genetics, including if you have the T allele for rs1049353 and other genes that contribute to food sensitivities. In addition, our reports and platform are the most cutting-edge solution in the personalized nutrigenomics space.
- LabTestAnalyzer can objectively tell you if the diet you’re eating is right for you. Check to see if your diet is keeping your labs optimal.
Note: This section contains links from our sister companies, SelfDecode and LabTestAnalyzer. SelfHacked is, in part, supported by purchases of these products. All proceeds get reinvested back into the company to help serve you better and improve the quality of our products, so we thank you for supporting us!
A carnivore diet is a good idea to try for a month if you have autoimmune or unexplained chronic inflammatory issues, or other health problems that you think might be caused by food.
In fact, we promote a lectin avoidance diet for people with food sensitivities. A carnivore diet limits almost all of the foods that people react negatively to. If you feel better on a carnivore diet, it’s wise to introduce foods back in and see what it is you’re reacting to. If you need to stay on a carnivore diet over the long run, we at SelfHacked suggest that you supplement with missing nutrients and polyphenols.
It may be possible to get all your nutrient requirements from a carnivore diet as long as such a diet includes organs (especially liver and sweetbreads) and seafood (especially salmon and mollusks). The most difficult nutrients to source from meat are vitamin C, boron, antioxidants, and fiber.
Besides nutrient deficiencies, the carnivore diet has other problems. Plant compounds trigger hormetic stress, which helps train your body to produce antioxidants and possibly live longer.
Most people are not sensitive to plant toxins and will do well on a diverse omnivorous diet. For the plant-sensitive minority, a carnivore-like diet may be worthwhile – just make sure you’re getting all of your nutrients.