Humans can eat whatever they want. Humans are opportunistic and can survive in very harsh conditions. They’ve survived for thousands of years including meat into their diet. But that doesn’t necessarily mean it’s the healthiest biological option. However, whether we’re biologically designed to eat meat is a different question. So lets look at whether or not if humans should eat meat by comparing the differences in mammals who are carnivores, omnivores, herbivores or herbivores.
The following is an incomplete list of the major differences between humans and carnivorous creatures.
Walking: We have two hands and two feet, and we walk erect. All of the carnivores have four feet and perform their locomotion using all fours.
Tails: Carnivores have tails.
Tongues: Only the truly carnivorous animals have rasping (rough) tongues. All other creatures have smooth tongues.
Claws: Our lack of claws makes ripping skin or tough flesh extremely difficult. We possess much weaker, flat fingernails instead.
Opposable thumbs: Our opposable thumbs make us extremely well equipped to collect a meal of fruit in a matter of a few seconds. Most people find the process effortless. All we have to do is pick it. The claws of carnivores allow them to catch their prey in a matter of seconds as well. We could no more catch and rip the skin or tough flesh of a deer or bear barehanded than a lion could pick mangos or bananas.
Births: Humans usually have children one at a time. Carnivores typically give birth to litters.
Colon formation: Our convoluted colons are quite different in design from the smooth colons of carnivorous animals.
Mammary glands: The multiple teats on the abdomens of carnivores do not coincide with the pair of mammary glands on the chest of humans.
Sleep: Humans spend roughly two thirds of every 24-hour cycle actively awake. Carnivores typically sleep and rest from 18 to 20 hours per day and sometimes more.
Microbial tolerance: Most carnivores can digest microbes that would be deadly for humans, such as those that cause botulism.
Perspiration: Humans sweat from pores on their entire body. Carnivores sweat from the tongues only.
Vision: Our sense of vision responds to the full spectrum of color, making it possible to distinguish ripe from unripe fruit at a distance. Meat eaters do not typically see in full color.
Drinking: Should we need to drink water, we can suck it with our lips, but we cannot lap it up. Carnivores’ tongues protrude outward so they can lap water when they need to drink.
Placenta: We have a discoid-style placenta, whereas the carnivores have zonary placentas.
Vitamin C: Carnivores manufacture their own vitamin C. For us, vitamin C is an essential nutrient that we must get from our food.
Jaw movement: Our ability to grind our food is unique to plant eaters. Meat eaters have no lateral movement in their jaws.
Dental formula: Mammalogists use a system called the “dental formula” to describe the arrangement of teeth in each quadrant of the jaws of an animal’s mouth. This refers to the number of incisors, canines, and molars in each of the four quadrants. Starting from the center and moving outward, our formula, and that of most anthropoids, is 2/1/5. The dental formula for carnivores is 3/1/5-to-8.
Teeth: The molars of a carnivore are pointed and sharp. Ours are primarily flat, for mashing food. Our “canine” teeth bear no resemblance to true fangs. Nor do we have a mouth full of them, as a true carnivore does. I am reminded of one of Abraham Lincoln’s favorite retorts: “If you counted a sheep’s tail as a leg, how many legs would it have?” Invariably, people would answer, “five.” To which Lincoln would respond: “Only four. Counting the tail as a leg doesn’t make it one.”
Intestinal length: Our intestinal tracts measure roughly 12 times the length of our torsos (about 30 feet). This allows for the slow absorption of sugars and other water-borne nutrients from fruit. In contrast, the digestive tract of a carnivore is only 3 times the length of its torso. This is necessary to avoid rotting or decomposition of flesh inside the animal. The carnivore depends upon highly acidic secretions to facilitate rapid digestion and absorption in its very short tube. Still, the putrefaction of proteins and the rancidity of fats is evident in their feces.
Saliva and urine pH: All of the plant-eating creatures (including healthy humans) maintain alkaline saliva and urine most of the time. The saliva and urine of the meat eating animals, however, is acidic.
Diet pH: Carnivores thrive on a diet of acid-forming foods, whereas such a diet is deadly to humans, setting the stage for a wide variety of disease states. Our preferred foods are all alkaline-forming.
Stomach acid pH: The pH level of the hydrochloric acid that humans produce in their stomachs generally ranges about 3 to 4 or higher but can go as low as 2.0. (0 = most acidic, 7 = neutral, 14 = most alkaline). The stomach acid of cats and other meat eaters can be in 1+ range and usually runs in the 2s. Because the pH scale is logarithmic, this means the stomach acid of a carnivore is at least 10 times stronger than that of a human and can be 100 or even 1,000 times stronger.
Uricase: True carnivores secrete an enzyme called uricase to metabolize the uric acid in flesh. We secrete none and so must neutralize this strong acid with our alkaline minerals, primarily calcium. The resulting calcium urate crystals are one of the many pathogens of meat eating, in this case giving rise to or contributing to gout, arthritis, rheumatism, and bursitis.
Digestive enzymes: Our digestive enzymes are geared to make for easy to initiate the digestion of fruit. We produce ptyalin – also known as salivary amylase – to intiate the digestion of fruit. Meat-eating animals do not produce any ptyalin and have completely different digestive enzyme ratios.
Intestinal flora: Humans have different bacterial colonies (flora) living in their intestines than those found in carnivorous animals. The ones that are similar, such as lactobacillus and e. coli are found in different ratios in the plant eaters’ intestines as compared to those of the carnivores.
Liver size: Carnivores have proportionately larger livers in comparison to their body size than humans.