Does The Carnivore Diet Work BBetter For Weight Loss, Health And Mood? Reviews Of Diets
The Carnivore Diet: Fantastic or Fanatical?
In recent times, the fitness industry has become obsessed with the carnivore lifestyle.
The advocates of this high-protein, low-carb, zero-carb diet wax lyrical on its purported benefits to improve health, body composition and mood.
A wealth of scientific literature suggests that a high intake of plant foods is consistently associated with a reduced risk of mortality from all causes[1].
In this installment of our “Diets Reviewed” series, we examine these claims to see if the carnivore lifestyle lives up to its hype.
What is the carnivore’s diet?
The carnivore diet is an extreme version, similar to the ketogenic diet. The carnivore approach is similar to the keto diet, but it completely excludes plant foods. Instead, it focuses on a high intake of meat, fish and eggs as well as a small amount of low-lactose milk products. Some carnivores may include ‘less toxic foods’ like olives or lettuce that they believe are less harmful.
Chicken, turkey, pork and lamb are all permitted foods, as well as offal, white and oily fish, hard cheeses, butter, and cream. To ensure you meet your daily energy requirements, experts recommend choosing fatty meat cuts. This is because carbohydrates can be a major contributor to your daily calorie intake. The carnivore’s diet is very restrictive, as it excludes all fruits, vegetables and grains. Forget the herby potatoes and wine with your steak.
Here is a quick overview of the foods you can eat on a carnivore’s diet:
James Salisbury was an American physician who is the name of the Salisbury Steak. He claimed that starchy and vegetable foods cause diseases in the body. He made the rather unbelievable claim that dysentery can be cured by drinking a lot of coffee and eating lean meat chopped up! [3]
Nevertheless, the belief that a diet high in meat is better for your health persists. Dr Paul Saladino is a modern carnivore who advocates the diet. He believes that “colourful plants cause inflammation in the body”[4]. Another of the diet’s leading proponents is Dr Shawn Baker, whose medical license has been revoked. Baker, a former Orthopaedic Surgeon, Air Force Officer and World Record-Holding Weight Lifter who wrote The Carnivore Diet is a former Air Force Officer. He claims that a diet consisting of only meat is “ancestrally consistent” with the diets of early humans. [5] Saladino, Baker and others believe they can improve their health and live longer by eating a diet they believe is consistent with the eating habits our ancestors.
Claims in the spotlight
Carnivores make many claims about the health benefits of a meat-only diet, but do these claims match up with the science?
1. Plants can contain harmful antinutrients
Baker and Saladino claim that plants have harmful levels of antinutrients which act as defense mechanisms. These include tannins, lectins and phytic acids, which prevent nutrient absorption[8]. Certain plant foods contain substances known as antinutrients. For instance, glucosinolates found in cruciferous veggies can reduce iodine intake and possibly impair thyroid function[9],[10]. This theory, however, ignores that modern cooking and preparation methods such as removing rice’s husk can remove or breakdown these antinutrients. These compounds are also rarely consumed in large quantities in isolation, and the plant foods that contain them contain thousands of beneficial substances such as antioxidants and vitamins.
2. The diet of early humans was a carnivore-based diet
Carnivores believe that the early man was primarily a meat eater and, therefore, we have evolved to be like him. The research shows that eating meat and hunting was an important step in the evolution of humans. Niacin or vitamin B3, a water-soluble version of vitamin B3, was responsible for increasing the size of the brain. Archaeological evidence shows that palaeolithic people ate fruits, tubers, and plants as well as hunting and eating game. This theory conveniently ignores that early humans lived only to about 40 years old[14].
3. A carnivore diet can improve body composition
Carnivore proponents argue that focusing the diet purely on meat and animal products improves body composition[15],[16]. High-protein diets are known to support fat loss by retaining lean mass and improving satiety[17]. It is easier to create a calorie surplus when you eliminate all processed foods. Research shows, however, that when the calorie intake and protein intake are equal, both high-carbohydrate and low-carbohydrate approaches result in an equivalent amount of fat loss[18]. The main factor in body composition is a negative energy balance, not the lack of plant-based food. It has been shown that diets high in fruit and vegetables are particularly effective at managing hunger, and therefore, adhering to a particular dietary strategy[19].
4. Carbohydrates are bad for you
The consumption of refined carbohydrates has been associated with everything from diabetes and obesity to heart disease[20]. It is becoming more widely accepted that a diet high in saturated fats as well as refined carbohydrates can be harmful to health. Complex starchy and fibrous carbohydrate have many health benefits. High-fibre grains and vegetables are rich in nutrients, fibres, and resistant starches which are vital for a healthy microbiome. Gut health plays a pivotal role in the management of many metabolic and autoimmune disorders, such as hypertension, type-2 diabetes, high cholesterol and Alzheimer’s. It is a contradiction to all scientific logic that if improved health is desired, high saturated fat intake, which increases risk of serious diseases, should be substituted for fibrous vegetables.
Carnivores: The downsides
1. The restrictions are very high
Carnivores are restricted in their diets, and they lack many essential micronutrients, antioxidants, and whole grains. You will not only miss out on flavour, variety and enjoyment but you may also suffer from serious nutritional deficiencies such as vitamin E, potassium, magnesium, and vitamin C.
2. High in saturated fat
Carnivores are known to consume a lot of meat that is high in saturated fat. Saturated fats are proven to increase cholesterol and heart disease risk[24]. We know, however, that eating a lot of unsaturated fats like avocado, olive oil, oily fish and nuts is a great way to maintain healthy blood triglyceride level[25].
3. This product does not contain any dietary fiber
A large body of research has shown that dietary fiber is essential for digestive health, mental well-being, insulin sensitivity and blood pressure. Increased fibre intake can reduce cardiovascular disease risk by as much as 25%, due to its positive effect on cholesterol metabolism and bloodpressure[27],[28].
4. You may have thyroid dysfunction
Research suggests that consistently consuming fewer than 50 g of carbohydrates per day can increase the risk of thyroid dysfunction, which can have various adverse effects on metabolism, energy levels, and body composition[29],[30],[31],[32]. The severity of this effect is directly proportional to the length and severity with which you have been on a super-low carb diet.
5. Certain populations are not suitable for this product
The carnivore’s diet is not recommended for those with kidney disease. This is because the kidneys play a crucial role in amino acid and proteins metabolism. The diet is also not suitable for pregnant women, children or nursing mothers because it lacks essential vitamins and minerals.
6. You may experience digestive problems
You may find that your bathroom visits are less frequent when you follow a carnivore’s diet, as there is no fiber to add water and mass to your stool. It’s also not uncommon for people to suffer from acute diarrhoea when their body is unable to cope with excessive fat levels[33]. This is due to the body not being able to produce enough of lipase (the enzyme that breaks fats down) and the lack of plant foods, which starves the good bacteria in the gut and increases the risk for infection.
7. It’s costly
It is because of their relative nutrient content, portability, and low price that carbohydrates are the basis for most food cultures. Baker’s Piedmontese Beef, which costs more than twice as expensive as similar cuts of meat, can be an unaffordable indulgence for many[35].
You will probably see a decline in your training performance
Low glycogen availability can be a major factor in fatigue, especially during intense exercise such as resistance training. If muscle gain is what you want, the body will adapt. However, there are more efficient and less restrictive ways to achieve this goal.
8. The environment may be affected
Meat consumption, industrial animal production practices and greenhouse gas emissions are all linked[38]. According to statistics, the carbon footprint of a pound of beef is 10 times greater than that of a pound of rice[39]. It’s not necessary to eliminate meat from your diet, but an all-meat intake is likely to be the most environmentally friendly.
Take-home message
Carnivores may be able to create a calorie surplus and improve their body composition by reducing hunger. It is important to note that limiting intake of plant-based food rich in nutrients can have a number of negative effects on physical and mental well-being. The carnivore’s diet is a dogmatic “diet culture” that has very few benefits for health and places a high level of restrictions. We would not recommend an all-meat approach based on health or performance.
Want to read more about our “Diets Reviewed” series? We dive deep into the science behind a meatless diet to help you consider all factors.
Takeaways
- The carnivore’s diet excludes all plant foods and only includes meat and animal products.
- Carnivores say that their diets are ‘ancestral’ and they avoid toxins in plant foods.
- Archaeological evidence shows that early man consumed a variety plant foods.
- Plant foods and fibres are essential for a variety of health conditions, including the mental, digestive, immune, and hormonal systems.
- It has been proven that a high-fibre intake correlates with a lower risk of mortality from all causes, such as cardiovascular disease, type II diabetes and high cholesterol.
- The carnivore dietary strategy does not promote weight loss as effectively as other strategies, but it may encourage calorie restriction.
- Carnivores are often viewed as unhealthy and restrictive.