Herbivorous Man

“It is only by softening and disguising dead flesh by culinary preparation that it is rendered susceptible of mastication or digestion; and that the sight of its bloody juices and raw horror, does not excite intolerable loathing and disgust. Let the advocate of animal food, force himself to a decisive experiment on its fitness, and as Plutarch recommends, tear a living lamb with his teeth, and plunging his head into its vitals, slake his thirst with the steaming blood.” (Percy Bysshe Shelley)

“Although most of us conduct our lives as omnivores, in that we eat flesh as well as vegetables and fruits, human beings have characteristics of herbivores, not carnivores.” (Dr. William C. Roberts, editor-in-chief, American Journal of Cardiology)

Dr. Milton Mills makes the following case for human beings as natural herbivores:


Nails are represented by sharp claws, serving an obvious purpose.

Mouth opening is large relative to head size, with reduced facial musculature to facilitate the seizing, killing, and dismembering of prey.

Jaw joint is a simple hinge. Lower jaw cannot move forward and has very limited side-to-side motion.

Teeth are spaced so stringy debris is not caught. Incisors are short and pointed for grasping and shredding. Canines are long and dagger-like for stabbing, tearing, and killing. Molars are triangular with jagged edges, like serrated blades.

Saliva does not contain digestive enzymes. Carnivores gorge rapidly and without chewing.

Stomach is very large relative to the rest of the digestive system (60-70% of GI tract) and has a high level of hydrochloric acid to facilitate protein breakdown and kill dangerous bacteria. Small intestine is short (3-5x body length). Colon: simple, short, and smooth (like a pipe, quick in-and-out); about the same diameter as small intestine; functions only to absorb salt and water.

Liver can detoxify vitamin A.

Kidneys have extremely concentrated urine.

Note: A true omnivore, such as a bear, exhibits the anatomy of a carnivore save for the squared molars used for crushing and grinding plant food.

Human Beings

Our hands, fingers, and flattened nails are ideally suited for picking fruits and vegetables, not ripping into a tough hide.

Mouth opening is relatively small, with the “muscles of expression” aiding the chewing process.

Jaw can move side-to-side for crushing and grinding and is easily dislocated, which would be a survival hindrance for carnivores.

Teeth are usually close together. Incisors are flat and spade-like for peeling and biting soft substances. Canines are flattened, blunt, and small. Premolars and molars are flattened and nodular for crushing, grinding, and pulping.

Saliva contains amylase to break down carbohydrates and digest starches. Esophagus is narrow and designed for small, thoroughly chewed bits of food.

Stomach is 21-27% of GI tract and is only moderately acidic. While true that we do not have the multi-chambered stomachs of ruminant herbivores, our larger intestines ferment the soft plant vegetation (ruminants typically eat tougher plants) in our diet, making the multiple chambers unnecessary. Small intestine is long (10-11x body length). Colon: long, pouched, and winds in three directions; has a greater diameter than small intestine; responsible for vitamin production and absorption.

Liver cannot detoxify vitamin A.

Kidneys have only moderately concentrated urine.

In short, our bodies do not allow for natural carnivorous feeding. We must cook our meat – not to mention doctor it in myriad ways – because to not would make us vulnerable to the life-threatening bacteria – Salmonella, E. coli, Trichinosis, Listeria – that true carnivores need not worry about. Author John Robbins: “If you were to swallow a capsule containing the digestive secretions of a cat, the contents of that capsule would be so acidic that they would almost instantly ulcerate the lining of your stomach.”

While true that our ancestors hunted and consumed animals, they did so out of necessity, a survival-mechanism borne of climate. But today, being an omnivore is a choice. Writer Harvey Diamond famously remarked, “You put a baby in a crib with an apple and a rabbit. If he eats the rabbit and plays with the apple, I’ll buy you a new car.” It really is that simple.