Are Humans Meant to be Vegetarian? A look at the science.

Over the years, in different situations, a handful of doctors and natural practitioners have recommended to me a meat-based diet, as a possible cure for various small and large ailments.  Along with that, some oft-quoted areas of concern (without a test, mind you!) are iron levels and vitamin B12.  Incidentally, lentils (which we eat a lot of!), beans, dark green leafy vegetables and figs are all excellent sources of iron.  Now, I'm a strict vegetarian in the sense that I will not eat flesh for any reason.  So, naturally if a doctor says that to me, I will scoff and seek another solution.  But that isn’t the reason for this discussion.  Let's set aside my personal bias and look at our own human physiology, especially our digestive system, as compared with natural carnivores and herbivores.

Physiology of a Carnivore:

*Long, pointed teeth suitable for tearing into flesh

*Short intestine, usually 1-3x the length of the body with relatively few twists and turns, optimized for getting meat through quickly so it doesn't putrefy in the gut, as well as highly acidic gastric fluids (20x more acidic than an herbivore) for easy digestion of cholesterol and saturated fats prevalent in animal food. No need for fiber to help things along because intestine is short.

*Highly acid saliva that contains no ptyalin (grain-digesting enzyme), less developed salivary glands

*Claws (as opposed to nails)

*Lap or lick water (as opposed to sipping)

*Perspire through tongue (skin has no pores)

*Great night vision suitable for hunting and sneaking up on prey


Physiology of an Herbivore:

*Flat incisors for clipping plants and molars for grinding grain

*Long intestine (10-12x the length of the body) with lots of twists and turns, suitable for absorbing the nutrients within grains (meat will putrefy in the gut of an herbivore 4 hours after ingesting), gastric fluids 20x less acidic than carnivores, little to no ability to break down saturated fats and cholesterol.

*Alkaline saliva and well-developed salivary glands that produced a grain-digesting enzyme, ptyalin

*Nails (no claws)

*Sip water (vs lapping or licking)

*Perspire through skin (not tongue)

*Night vision is relatively poor.

Which category do humans belong in?  You decide.  I know, all the evidence here is stacked toward humans being natural herbivores.  That’s just the way it is, folks!  I’ve never seen a compelling argument for humans to be natural-born meat-eaters.

Okay, if you're a staunch carnivore or omnivore yourself, (or even an admittedly convenient one) you're certainly entitled to your opinion, and your habits.  Diversity is the spice of life, after all.  But just for fun, here are all the “humans are meant to be omnivores” arguments I’ve ever seen or heard, and my rebuttals to them!  

1. Neanderthals (our closest hominid relatives) were big meat eaters, so we must be too!
Well...are you a Neanderthal?  Last time I checked, I wasn't.  I don't know about you.  Whether we evolved from Neanderthals or not (which is a debatable theory, whether or not you are a creationist) you are (most likely) not a Neanderthal now and maybe shouldn't eat like one.

2. "Most" of the arguments for being vegetarian are based on morality or us being related to chimpanzees. 
Do you see anything about chimps (or morality for that matter) above?   I don't, unless you think the herbivore generalizations meant chimps only! Oh...or if you think it's moral to have molars instead of long sharp teeth.

3. O blood types were naturally hunter-gatherers and need to eat meat to be healthy.
While the blood type diet is a noble idea, it isn't a complete theory, and the science behind early humans being hunter-gatherers is purely erroneous.  Unfortunately in the West we are ridden with so-called "science" that is half baked and doesn't take into account the tens or hundreds of thousands of years of history of humanity and our eating habits for that entire period of time.  For many thousands of years before "hunter-gatherers" graced the fertile crescent, humanity in so-called "pre-historic" (read pre WESTERN) societies (aka India, China, etc) engaged in agriculture.

4. I feel better when I eat meat, so it must be natural to me, and everyone else who chooses not to eat it is denying some basic instinct.

Um, I'm not going to argue with your comfort level or preference.  But, if you're comfortable with it, it's because you grew up eating it and so, yeah, it's a comfort food.  But as for everyone else...they can speak for themselves.  I'll speak for myself...meat (uh, like roadkill? or other dead flesh?) is gross. I became a vegetarian 13 years ago, almost out of curiosity.  When I did, I was afraid my hair would lose its lustre and my nails would get brittle, or my skin would turn ashy.  Au contraire!  My nails grew better, my hair got more volume and lustre and my skin, while okay before, began positively to glow.  And it was a benefit not only in terms of vanity.  Food tasted better too!  While before, there was black and white (the meat and non-meat), food turned to a multitude of tastes, textures and colors.  I have never eaten better than since I've been vegetarian.  Oh, and, rumor has it, vegetarians smell better, too.

5. You need animal fat to be healthy.
While the "Nourishing Traditions" Sandy Fallon Weston A Price diet is well-intended and a nice idea for returning to nature, its bias is based solely on dental study of ONE culture.  It does not take into account other cultures, who for thousands of years have been flourishing vegetarians. Furthermore, it is unscientific in that it does not take into account the other lifestyle aspects of that culture.  It isn’t “double blind” in other words. Don’t get me wrong—that book provides a lot of useful information on the benefits of raw and fermented foods (which have their own arguments in favor).  I’m a raw milk drinker myself, a homemade kefir drinker and extol the benefits of both to many I come across.  Also that book provides a lot of useful information on soaking grains for maximum digestibility and enzyme benefits.  Its basis for looking to ancient cultures for good nutrition is exemplary.  Much can be learned from it, but the meat and dairy argument is not the be-all end-all.

If there's a good meat-argument I left out, feel free to comment!  Let's go head on!

And now for a very handy resource:

Vegan and one Lacto-vegetarian source of B-12!

Vitamin B12 sources are an oft-made-fun-of area for vegetarians, vegans especially.  It is the popular belief that there is NO vegan source of B12, and that it only comes from meat or supplements. 
This is completely wrong! Vitamin B12 occurs through the process of fermentation and has little to do with the medium it is grown in.  Here is a list of some of my favorite vegan and vegetarian whole food B12 sources that are easily obtainable.

*Idli and dosa (south indian lentil/rice patties and pancakes) made by grinding and fermenting rice and lentil, then cooking. Incidentally, these are also the only food known to humankind (or at least that I know of) that contains all 22 amino acids in a single source.  (note: easy packaged idlis and dosa don’t have it, you have to ferment them to get the full benefit!)

*Chlorella tablets or powder (a green algae --great for you anyway, they also have a complete amino acid profile and as well detox you from a multitude of things including heavy metals.) Okay, I confess this one comes in a bottle and is considered a supplement.  But, it offers plenty of benefits in addition to B12, and it really is a whole food.  It’s an algae after all.

*Nutritional yeast (get this in the bulk section of your natural food store, tastes great on popcorn or in a sauté broth; with tofu and brocolettes is my favorite.)

*Leave a glass of cooked rice on the counter overnight in water.  In the morning it will have the full B complex.  All you need to do is drink the water in the glass. You can eat the rice too. (Thanks, Meenakshi!)

*Miso (a superhealthy, high protein, digestible soy or chickpea food!) makes great soup and dressing, best consumed raw.

*Homemade kefir (only if you drink milk) - I don't know whether tibicos/water kefir contains any B12.  I haven't found any information on that.

*Most any fermented food can be cultured with “Aspergillus oryzae.” This is a botanical name for Vitamin B12.  You can look for this on labels. It might also appear on tempeh labels and those of other interesting fermented vegetarian foods. Heck, maybe you could even throw it in kimchee or sauerkraut!


Suggestions for further reading on these topics: