What is a person called when they only eat meat? A Deep Dive into the Carnivore Diet

January 11, 2026 •

4 min read

For generations, some Arctic populations have subsisted almost entirely on animal-based diets. A person who adopts a similar meat-only eating pattern is colloquially known as a 'carnivore', though this is a modern dietary movement with significant biological and health considerations.

Quick Summary

A person exclusively consuming meat and animal products is often termed a carnivore. This article examines the modern Carnivore Diet, its principles, potential short-term benefits, and considerable long-term risks identified by health professionals.

Key Points

Term Definition: A person who chooses to eat only meat is colloquially called a 'carnivore', but biologically, humans are omnivores.
Dietary Scope: The Carnivore Diet involves consuming exclusively animal products like meat, fish, eggs, and certain dairy, while eliminating all plant-based foods.
Purported Benefits: Short-term benefits reported by followers include weight loss, reduced inflammation, and improved mental clarity, though these are largely anecdotal.
Significant Risks: Health experts warn of potential long-term risks, including nutrient deficiencies (especially fiber and vitamin C), high saturated fat intake, and kidney strain.
Long-term Sustainability: The diet is highly restrictive and lacks supporting long-term clinical research, making it difficult to sustain and potentially dangerous for overall health.
Professional Guidance: It is crucial to consult a healthcare professional before attempting such a restrictive diet due to the significant health risks and unknown long-term effects.

Defining a Human 'Carnivore'

While the term 'carnivore' biologically refers to an animal that eats only other animals, its application to humans is more complex. Biologically, humans are classified as omnivores, meaning our bodies are adapted to digest both plant and animal matter. Our dental structure, featuring incisors for cutting, canines for tearing, and molars for grinding, reflects this versatility. The human digestive system also showcases adaptations for a mixed diet, with a stomach acidity level falling between strict herbivores and true carnivores.

When a person adopts a diet consisting exclusively of animal products, they are colloquially referred to as following the 'Carnivore Diet', sometimes known as a 'zero carb' or 'all-meat' diet. It's crucial to distinguish this intentional dietary choice from a species' biological classification. While a domestic cat is an 'obligate carnivore' that must eat meat to survive, a human on a carnivore diet is still biologically an omnivore, choosing to restrict their diet.

The Modern Carnivore Diet: Foods and Restrictions

The Carnivore Diet is a highly restrictive eating plan that eliminates all plant-based foods. Its proponents claim it can help with various health issues, though these claims are largely based on anecdotal evidence rather than robust scientific studies.

Here are the typical rules of the diet:

Foods to eat: The diet is centered on animal products. Permissible items include meat (beef, pork, lamb, chicken), fish (salmon, sardines), eggs, and some low-lactose dairy (butter, hard cheese, heavy cream). Organ meats like liver and bone broth are also encouraged for nutrients.
Foods to avoid: All plant-based foods are completely excluded. This includes vegetables, fruits, legumes, grains, nuts, and seeds. Sugar, refined carbohydrates, and most processed foods are also banned.
Macronutrient focus: The diet is inherently high in protein and fat, with nearly zero carbohydrates. This forces the body into a state of ketosis, where it burns fat for fuel instead of glucose.

Reported Benefits and Anecdotal Claims

Advocates of the Carnivore Diet point to a number of potential benefits, though a significant portion of this evidence is anecdotal. Some common claims include:

Weight Loss: The high protein and fat content can increase satiety, leading to reduced calorie intake and weight loss. The initial weight loss is often water weight as the body depletes its glycogen stores.
Reduced Inflammation: Followers report improvements in inflammatory and autoimmune conditions by eliminating potential plant-based triggers like lectins and oxalates.
Improved Mental Clarity: Some individuals experience enhanced focus and reduced 'brain fog', which is often attributed to stabilized blood sugar levels and the state of ketosis.
Digestive Improvements: Removing fermentable fibers found in some plant foods can lead to less bloating and gas for some individuals, particularly those with sensitivities.

Health Risks and Nutritional Concerns

Despite the positive anecdotal stories, most health professionals and dietitians raise serious concerns about the long-term sustainability and safety of a strictly meat-only diet.

Potential long-term health issues:

Nutrient Deficiencies: The diet eliminates entire food groups that provide essential nutrients. A significant lack of fiber and antioxidants can lead to gut microbiome imbalance and poor digestive health. Deficiencies in vitamins like C and K are also a serious concern.
High Saturated Fat and Cholesterol: A diet centered on meat is often high in saturated fat and cholesterol, which can elevate LDL ('bad') cholesterol levels and increase the risk of heart disease.
Kidney and Liver Strain: The high protein intake places increased stress on the kidneys and liver, which must work harder to process waste products. This can increase the risk of kidney stones and long-term organ damage.
Constipation: The complete lack of dietary fiber, which is crucial for healthy bowel movements, is a common and predictable side effect.
Lack of Long-Term Studies: The long-term effects of this diet on human health are largely unknown and understudied. Most of the available data is from short-term anecdotes.

Carnivore vs. Omnivore vs. Herbivore: A Comparison


Attribute	Carnivore (Animal)	Omnivore (Human)	Herbivore (Animal)
Primary Food Source	Exclusively animal flesh	Both plants and animals	Exclusively plants
Digestive System	Short intestinal tract; high stomach acidity; lacks enzymes for plant digestion	Variable intestinal tract; moderate stomach acidity; can digest both plants and animals	Long intestinal tract; specialized fermentation chambers (in some species) for plant matter
Dental Structure	Pronounced canines and sharp molars for tearing and shearing meat	Mixed dentition: incisors for cutting, canines for tearing, and flat molars for grinding	Large, flat molars for grinding fibrous plant material; sometimes large incisors
Nutrient Requirements	Requires nutrients found only in animal flesh (e.g., preformed vitamin A, taurine)	Can obtain nutrients from a variety of plant and animal sources	Requires nutrients found in plants, often synthesized with gut bacteria

Conclusion

While a person who only eats meat is commonly referred to as a 'carnivore', this is a modern and restrictive dietary choice, not a biological classification. As humans, we are naturally omnivores, and following a meat-only regimen, such as the Carnivore Diet, is a significant departure from a traditional balanced diet. The diet's reported benefits, while compelling to some, are largely based on anecdotal evidence, and the potential for long-term health risks is substantial and supported by nutritional science. Individuals considering this extreme dietary approach should do so with extreme caution and in consultation with a healthcare professional or registered dietitian. Eating a balanced, varied diet remains the most recommended approach for long-term health and wellness. For more information on the medical perspective regarding the Carnivore Diet, refer to this article from Harvard Health.

Frequently Asked Questions

No, humans are biologically omnivores, with a digestive system and dental structure capable of processing both plant and animal matter efficiently.

A biological carnivore, like a cat, must eat meat to survive. A human on a carnivore diet is still an omnivore who chooses to restrict their diet, and they can technically survive without meat, unlike an obligate carnivore.

No, there is very limited high-quality research on the long-term health effects of the Carnivore Diet. Most positive claims are anecdotal, and health professionals express serious concerns about nutritional deficiencies and other risks.

Significant risks include a lack of dietary fiber, which can cause constipation and gut microbiome issues, as well as deficiencies in essential vitamins like C and K, and potential stress on the kidneys and heart due to high protein and fat intake.

The diet includes all forms of meat, fish, eggs, and some low-lactose dairy products. Proponents often recommend fatty cuts and organ meats to provide some essential vitamins.

The Carnivore Diet can lead to ketosis because it contains almost no carbohydrates, but it is much more restrictive than a standard ketogenic diet, which typically includes many plant-based foods.

Some individuals may feel better in the short term due to the elimination of processed foods and common dietary irritants. High protein intake can also lead to increased satiety and reduced sugar cravings.

While trace amounts of vitamin C can be found in organ meats, the Carnivore Diet is generally deficient in this crucial nutrient, as it is primarily found in plant-based foods.