What is the Proper Diet for Human Beings?

The optimal diet for human beings should be one that makes us look, feel, and function our best, prevent us from getting sick, and allow us to live long lives with a quick and painless death. All of these symptoms of an optimal diet are nearly nonexistent in the high-meat, high-dairy, highly processed foods of the Western diet.

Not being able to control your bowels, losing your muscle and motor skills, loosing eyesight, and forgetting things are widely assumed as the normal effects of old age. But all of these symptoms are actually poor diet and lack of exercise catching up with you.

If you want to see what it's like to be healthy at 100 years of age watch this video.

Our Anatomy and Physiology is Designed For Plants1-7

If you look at the human body, you'll find we share an enormous amount of similar traits with herbivores, and little to none with flesh-eating animals. True omnivores like bears, raccoons, and dogs have an anatomy and physiology similar to carnivores, with a few adaptations to allow them to eat plant foods.

For example, flesh-eating animals (like dogs) lick up water with their tongue, they do not have the muscles required to suck water into their mouths like elephants, horses, and humans. Flesh-eating animals also cool their bodies by panting, while herbivores cool their bodies by sweating. We have little in common with omnivores.

We Have the Mouth of a Plant Eater

Many meat-eaters believe that because we have canine teeth it automatically makes us omnivores. But these "canine teeth" are canine in name only. Our canine teeth are flat, blunted, and shaped like a spade, perfect for biting and peeling soft fruit, just like that of an herbivorous horse or gorilla. Real canine teeth are conically shaped and really long and really sharp.

The teeth of flesh-eating animals interlock like numerous pairs of scissors (like interlocking your fingers), perfect for ripping and tearing raw flesh from bone. The teeth of plant-eating animals sit on top of each other, perfect for grinding and chewing fibrous plant foods.

The jaws of natural meat-eating animals only move up and down, all of the muscles are concentrated on biting with tremendous force and not allowing struggling prey to escape. Instead of moving their jaw side to side, they have huge neck muscles for thrashing their necks to rip apart flesh and guts. The strongest muscle of most meat-eating animals, like dogs, is their neck. This, along with their sharp, fang-like teeth are perfect for holding onto flailing prey that are trying to escape. Their teeth are perfect for ripping apart flesh from bone and swallowing their food whole, no chewing necessary.

  1. Human
  2. Cow
  3. Cat
  4. Dog
  5. Horse

In relation to how big their head is, meat-eating animals have a very large mouth opening. Compare how far the mouth of this omnivorous bear can open compared to your mouth. Also take note of how a bear, cat, and dog's canine teeth differ from your "canine teeth."

Herbivores have muscles for chewing foods while carnivores have muscles for biting and ripping apart raw flesh. Our jaws move side to side to chew up extremely fibrous plant foods. We have relatively weak necks, but an extremely strong tongue to help move the food around. The so called "muscles of expression" — how humans can make so many different faces — are really the many different muscles of chewing.

Because herbivores chew up their food into a pulp before swallowing it, we have no need for a large, carnivore-like, esophagus. If we do not chew our food enough, we can choke on it (mostly from eating too fast). About 4,000 people in America die every year of choking.8 The most common food to choke to death on is meat. Do you think animals who are designed to consume meat ever choke from not chewing it enough? No, they swallow it whole!

Our Digestive System is Optimized for Plant Foods

From our lips to our anus, our digestive system has evolved to efficiently digest and assimilate plant foods. Digestion begins in our mouth where a salivary enzyme, called ptyalin, begins to breakdown the complex carbohydrates of plants into simple sugars. Meat does not have any carbohydrates so carnivores have no need of this enzyme.

Because the enzyme to digest protein, proteolytic, is extremely acidic, if it were present in the saliva it would damage the oral cavity. Carnivores have no need for digestive enzymes in their saliva, they bite off huge chunks of meat and swallow them whole.

To properly digest flesh foods, the stomach of carnivorous animals contain huge quantities of hydrochloric acid. This acid is helpful in killing the abundance of bacteria found in decaying flesh foods, as well as bone. It's a good thing flesh is easily digested, due to the lack of fiber, because it decays rapidly (see how long that raw chicken breast stays good outside your refrigerator). For this reason, the intestines of flesh-eaters must be very short to excrete the remnants quickly before they rot. Omnivores, for example, have intestines that are 4-6 times their body length.

Because of the relative difficulty of digesting high fiber plant foods, herbivores have much longer intestines, about 10-12 times their body length. This gives the body plenty of time to breakdown and extract all the essential nutrients from the food. Human intestines are about 10-11 times our body length.

There is Nothing in Meat We Can't Get Somewhere Else.5,9

Many people believe, due to the meat and dairy industries huge marketing budgets, that meat is a necessary part of our diet — in other words, essential. But this simply is not true.

Because the human diet has consisted almost entirely of plant foods, we, as well as other herbivores, have the ability to synthesize nutrients that are only found in flesh. For example, herbivores are able to make Vitamin A from a precursor found in large quantities in plants, beta-carotene. Carnivores have no need to turn beta-carotene into Vitamin A because meat contains large doses of this vitamin. Niacin is another vitamin that is found in large quantities of flesh that carnivores have lost the need to synthesize. Herbivores synthesize Niacin from tryptophan which is found in large quantities of plants.

When humans do not eat enough Vitamin C, found in an abundance in plant foods, we get scurvy. Because there is no Vitamin C in flesh foods, carnivorous animals are able to synthesize it in their body from the various raw materials in their diet. Therefore, Vitamin C is not an essential nutrient for carnivores; they do not need to get it from their diet.

Our Instincts Are for Plants

When you see a dead bird on the side of the road, do you think about stopping for a snack? Does the idea of chasing an animal, catching it, and tearing it limb from limb while you feast on it's warm blood and guts excite you? Would you eat a dog or a cat or a horse? What makes cows and chickens so special? Do you enjoy the taste of raw flesh? If you answered yes to any of these questions, many people would think you deserve to be in an insane asylum.

We humans have no taste buds for flesh foods. If you try to give a carnivore (like a cat), a grape, it won't eat it because it does not have taste buds for carbohydrates. Similarly, we do not have taste buds for amino acids (protein), and need to alter flesh from its natural form by cooking it in sauces, spices, and/or fat to make it palatable. If you don't believe me, I would love to watch you try to eat a portion of boiled chicken or steak without adding anything to it. After noting your displeasure and inability to do so, I will give it to a dog or cat and watch as it eagerly wolfs it down.

Eating Meat Makes Your Life Giving Organs Not Work As Well

Here's a quote from a Dr. John McDougall, MD, newsletter:

"Men traditionally have been the hunters who carry back the slain animals to feed the village — you know, “they bring home the bacon.” Scientific research confirms meat is viewed as a superior masculine food.10 The acts of killing, butchering and eating animals are associated with power, aggression, virility, strength, and passion — attributes desired by most men — and eating meat has long been associated with aggressive behaviors and violent personalities. Men say they need more, and they do eat more meat, especially more red meat, than women. However, based on male anatomy, real men should be vegetarians.

Eating meat diminishes sexual performance and masculinity. The male hormone testosterone that determines sexual development and interest has been found to be 13% higher in vegans (a strict plant diet — no animal products of any kind) than in meat-eaters.11 Meat-eaters are likely to become impotent because of damage caused to the artery system that supplies their penis with the blood that causes an erection.12 Erectile dysfunction is more often seen in men with elevated cholesterol levels13, a condition related to habitual meat-eating.

The greatest threat to a man’s virility is from the high levels of environmental chemicals concentrated in modern meats of all kinds. These chemicals interfere with the actions of testosterone. Decreased ejaculate volume, low sperm count, shortened sperm life, poor sperm motility, genetic damage, and infertility result from eating meat with estrogen-like environmental chemicals14. These chemicals in the meat, eaten by his mother, influence the development of the male fetus, increasing the risk that the baby boy will be born with a smaller penis and testicles, as well as deformity of the penis (hypospadia) and an undescended testicle (cryptorchism). Estimates are 89% to 99% of the chemical intake into our body is from our food, and most of this is from foods high on the food chain — meat, poultry, fish, and dairy products."15,16

Now, this may have less to do with the quality organic meat as it does with the abundance of extremely low grade meat that is so pumped full of chemicals that it decreases our ability to create life. Unless you are buying expensive organic meat, it will contain these poisons.

Fast food and other restaurants are trying to make a profit, they will buy whatever meat is cheapest (unless the restaurant specifically states it's organic meat). And the cheapest meat is farmed in a factory where they load up the animals with growth hormones, antibiotics, and other chemicals that then get transferred into the consumer's body. Not good.

The More Meat You Eat the Greater Your Risk of Disease

Through immense scientific research, like the China Study, it has been made abundantly clear that the more animal-based foods we eat, the greater are risk for just about every kind of disease and illness in modern society. Dr. McDougall has had first-hand experience with curing many of his clients "incurable" diseases just by switching them to a whole foods vegetarian diet, with minimal or no dairy.

Meat takes the place of fruits and vegetables which contain large amounts of antioxidants that help keep us healthy. Diseases like cancer thrive in a low oxygen environment, antioxidants help bring oxygen to all parts of the body. Because we have to cook meat, it is devoid of all of it's life-preserving enzymes that are just as important, if not more, in the preservation of health.

What About B12?

Many meat-eaters throw the B12 argument as a last ditch effort on why we should eat meat. First of all, many people, regardless of whether or not they eat meat, are deficient in B12.

B12 exists in large quantities in organic top soil. Chemically grown food destroys the top soil and the B12 with it. As a result, livestock are fed foods fortified in B12 to make up for the large amounts of commercially grown foods.

B12 can only be synthesized by bacteria, and throughout your digestive system you have these B12 producing bacteria. But is this enough?

If you pull an organic carrot out of the ground and don't wash it too thoroughly, you are almost guaranteed to get a large quantity of B12. But because modern society has become so anal about washing our fruits and vegetables, these natural sources of B12 have nearly vanished.

Because of the B12 producing bacteria inside of us, it is very rare for healthy vegans to become B12 deficient (just because you don't eat meat doesn't mean you're eating healthy!). Our bodies can store B12 for long periods of time, but some doctors recommend taking a B12 supplement if you have been vegetarian for awhile. Click here to find out more about B12.

Return from Natural Herbivores to Healthy Eating

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2. The Comparative Anatomy of Eating, Milton R. Mills, M.D., EarthSave.ca, accessed Jan. 2009.
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6. W. Collens, “Phylogenetic Aspects of the Cause of Human Atherosclerotic Disease,” Circulation (suppl II) 31-32 (1965): II-7.
7. Carpenter KJ. Protein requirements of adults from an evolutionary perspective. Am J Clin Nutr. 1992 May;55(5):913-7
8. H. Heimlich, “A Life-Saving Maneuver to Prevent Food-Choking,” JAMA 234 (1975): 398-401.
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Allen NE. Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men. Br J Cancer. 2000 Jul;83(1):95-7.
12. Feldman HA. Erectile dysfunction and coronary risk factors: prospective results from the Massachusetts male aging study. Prev Med. 2000 Apr;30(4):328-38.
13. Bodie J. Laboratory evaluations of erectile dysfunction: an evidence based approach. J Urol. 2003 Jun;169(6):2262-4.
14. Rozati R . Role of environmental estrogens in the deterioration of male factor fertility. Fertil Steril. 2002 Dec;78(6):1187-94.
15. Duarte-Davidson R. Polychlorinated biphenyls (PCBs) in the UK population: estimated intake, exposure and body burden. Sci Total Environ. 1994 Jul 11;151(2):131-52.
16. Liem AK. Exposure of populations to dioxins and related compounds. Food Addit Contam. 2000 Apr;17(4):241-59.