Barry Groves: Man is a carnivore

Barry Groves, PhD in nutritional science, was a British researcher and author who dedicated his life to exposing the flaws in modern dietary advice. He was one of the most outspoken critics of the fear of fat and carbohydrate dominance that characterizes today's nutrition policy.

Through books, articles and lectures, he argued that humans are a flesh-eating animal, a true carnivore – not an "omnivorous" one who needs a balance between meat and plants, but a species biologically and physiologically perfectly adapted to a fat- and protein-based diet.

In the lecture Homo Carnivorous: What We Are Designed to Eat (see the video at the bottom of the article) he presented evidence that humans, like all other mammals, actually live on fat – although some animals eat plants purely mechanically. He showed how the modern concept of diet has been completely turned on its head, and that we must look to evolution to understand what humans are actually designed to eat.

Humans are not herbivores – we are carnivores

Groves begins his talk by explaining how human anatomy and physiology are completely incompatible with a plant-based diet. He compares our digestive systems to those of carnivores and herbivores, pointing out several crucial differences:

• Short intestine: Humans have a short gut, similar to carnivores, designed to digest and absorb nutrients quickly. Herbivores have long guts to be able to ferment and extract energy from large amounts of plant material over time.
• High stomach acid: Human stomach acid is extremely acidic, comparable to that of carnivores and scavengers. This is necessary to break down meat and kill bacteria in raw meat. Herbivores have much milder stomach acid, as they do not need to break down animal protein or protect themselves from meat-borne pathogens.
• Enzymatic adaptation: Humans produce pepsin and lipase, which are specific enzymes for digesting protein and fat. We do not have the enzymes needed to break down cellulose, which would be necessary if we were designed to eat plants.

Groves made it clear that the claim that humans are “omnivores” is a misconception. Yes, we can eat plants, but we are not adapted to live off them – just as a dog can eat bread, but is not made for it.

All mammals live on fat – even herbivores!

The most fascinating part of Groves' talk was his explanation of how Mammals are fundamentally fat eaters – even those that mechanically eat plants. This is a point that completely tears down the traditional understanding of herbivores and what they actually eat.

Groves divided herbivores into two groups based on how they are able to utilize the energy in plants:

Ruminants (pre-fermenters, e.g. cows, sheep and deer)

• These animals have specialized stomach chambers (like rumen) full of bacteria that ferment plant material.
• These microbes break down cellulose and convert it into short-chain fatty acids such as acetate, propionate and butyrate.
• The cow eats grass, but does not live off it – it lives off the fat that microbes produce from the grass.

Hindgut fermenters (rear fermenters, e.g. horses, gorillas and rabbits)

• These animals have a large colon and a huge "caecum" where microbes ferment fiber into the same fatty acids as in ruminants.
• Here too, it is not the plant material itself that provides energy, but the fat produced by microbes.

This means that no mammals actually live on plants – they live on fat.

Herbivores have developed specialized systems to extract fat from plant foods, but without microbes they would not be able to survive.

Humans, however, have rejected these systems. We are left with a small, useless appendix and a short colon. The appendix was millions of years ago our cecum, which gorillas have for fermentation, and as we naturally understand, we have long since stopped using it, so it has shrunk to nothing.

We therefore have no remaining mechanism for fermenting plant material into fat, as all herbivores have.

This means that we are not designed to eat plants as our main food, but instead are designed to consume fat directly, in its most accessible form: animal fat, just like dogs, lions, and tigers.

The narrow waist of man

All herbivores must eat all day long, to consume the large quantities of nutrient-poor grass and plant material, and they are as huge as barrels to accommodate the massive systems for fermentation.

The healthy human animal, on the other hand, is narrow around the waist, just like any predator that eats extremely nutrient-dense food. The predator does not need to eat all the time – perhaps only once a day, and perhaps not even every single day out in the wild.

If, however, we have fermented some plant food, this first takes place in the large intestine, where the body sends what it considers waste – because here we cannot absorb nutrients; only a balancing of salts and fluid takes place before it goes into the bowl.

All our nutrition is absorbed in the small intestine, and we have no system for digesting plants there, neither microbes nor enzymes.

The problem with fiber and plant-based diets

Groves also debunked the myth that fiber is necessary or beneficial. He explained why fiber is not only unnecessary, but downright harmful:

Causes intestinal problems: Fiber ferments in the colon and causes gas, bloating, and irritation. Many people find that their stomachs feel better when they cut out fiber.

The illusion of satiety: Many people claim that fiber makes you feel full, but this is an illusion. Fiber fills your stomach, but your body is not stupid – it knows that satiety is about sufficient fat, protein, vitamins and minerals, not about being stuffed with indigestible plant matter.

Blood sugar and diabetes: Fiber is often promoted as good for blood sugar control, but this is misleading. It only slows down the rise in blood sugar, but instead leads to chronically elevated blood sugarThis may be worse than short-acting insulin, especially for those with metabolic disease.

Barry Groves' Legacy – An Awakening for Nutrition Research

Barry Groves was a pioneer in exposing how modern nutritional advice violates our biological heritage. His research and lectures, including Homo Carnivorous, has inspired thousands to question established dogmas and return to a more natural and evolutionarily adapted diet.

He showed that:

Man is a carnivorous animal, with all biological characteristics adapted to animal food.

All mammals live on fat: Even those who eat plants, and we have discarded the ability to ferment plant material into fat.

Fiber is not necessary and can be harmful, and a diet rich in fat and protein is far more optimal for health.

Traditional human diets: Groves pointed out that traditional human diets often consisted of 60-80% of energy from fat, 20-25% from protein, and 0-15% from carbohydrates. This contrasts with modern dietary recommendations that promote higher carbohydrate intake.

Kleiber's law and human metabolism: He referred to Kleiber's law, which describes the relationship between body size and metabolic rate, to illustrate that the human brain has a disproportionately high energy expenditure compared to other species. This requires an energy-dense diet, which supports the idea of ​​a high-fat, high-protein diet.

Essential fatty acids for brain development: Groves emphasized the importance of long-chain fatty acids (such as DHA and EPA) for brain development and function. He argued that these fatty acids only are found in animal products, and that human evolutionary success is linked to the intake of such nutrients.

Biblical references to fat consumption: To illustrate humans' historical preference for fat, Groves referenced biblical texts in which fat was considered valuable and was offered to God, indicating its importance in early human societies.

Criticism of modern diet: Groves argued that the modern diet, which is often high in carbohydrates and low in fat, is responsible for the rise in chronic diseases such as heart disease, diabetes and obesity. He believed that a return to a more traditional, fat-based diet could improve public health.

Watch his lecture here:

See his website here

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Photo: Clara Molden

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