Human Ancestors Were Nearly All Vegetarians

[one...two...tree 2,762]

Paleolithic diets have become all the rage, but they are getting our ancestral diet all wrong.

Right now, one half of all Americans are on a diet. The other half just gave up on their diets and are on a binge. Collectively, we are overweight, sick and struggling. Our modern choices about what and how much to eat have gone terribly wrong. The time has come to return to a more sensible way of eating and living, but which way? An entire class of self-help books recommends a return to the diets of our ancestors. Paleolithic diets, caveman diets, primal diets and the like, urge us to eat like the ancients. Taken too literally, such diets are ridiculous. After all, sometimes our ancestors starved to death and the starving to death diet, well, it ends badly. Yet, the idea that we might take our ancestral diet into consideration when evaluating the foods on which our organs, cells and existence thrive, makes sense. But what did our ancestors eat?

Here is where the trouble starts. Collectively, anthropologists have spent many a career attempting to hone in on the diets of our most recent ancestors. Typically, they focus on our stone age (AKA Paleolithic) human ancestors or our earlier pre-human, hominid ancestors. Even if we just consider our stone age ancestors—those folks whose stories span the time between the first stone tool and the first agriculture—the sides of the debate are polarized. If you listen to one camp, our ancestors got most of their nutrition from gathered fruits and nuts; successful kills of big mammals may have been more of a treat than an everyday reality. A paper out just this month suggests even Neanderthals–our north country cousins and mates– may have eaten much more plant material than previously suspected. Still, the more macho camps paint a picture of our ancestors as big, bad, hunters, who supplemented meaty diets with the occasional berry “chaser.” Others suggest we spent much of our recent past scavenging what the lions left behind, running in to snag a half-rotten wildebeest leg when the fates allowed. Although “Paleolithic” diets in diet books tend to be very meaty, reasonable minds disagree as to whether ancient, Paleolithic diets actually were. Fortunately, new research suggests a clear answer to the question of what our ancestors ate.

The resolution does not come from new discoveries by archaeologists. It comes from context. When we talk about “paleo” diets, we arbitrarily tend to start with one set of ancestors, our most recent ones. I want to eat like ** erectus or a Neanderthal or a stone age human, my neighbors testify. But why do we choose these particular ancestors as starting points? They do seem tough and admirable in a really strong five o’ clock shadow sort of way. But if we want to return to the diet our guts and bodies evolved to deal with, we should not be looking at our most recent ancestors. Instead, we need to understand the diet of our ancestors during the time when the main features of our guts, and their magical abilities to turn food into life, evolved. We need, in other words, to look at apes, monkeys and other non-human primates.

I should start by explaining what the “gut” is and does; I use the term too loosely. What I really mean is the alimentary canal and all of its gurgling bells and whistles. This canal is the most important and least lovely one on Earth. It takes you from the mouth through the body all the way down to the #######. But while most canals take the shortest course between two points, the one inside you takes the longest. The longer the canal, the more area over which digestion can occur. Food enters the canal through the mouth, where it is chewed and slimed with saliva. It then hits the stomach, where much of the digestion of proteins occurs. Next, it is on down to the small intestine where simple sugars are absorbed. If you have just eaten a twinkie, the process essentially ends there. Everything worth consuming has been absorbed. But if you have eaten broccoli or an artichoke, things are just beginning. It is in the large intestine, where harder to break down carbohydrates (such as cellulose, the most common plant compound on Earth) are torn asunder. This system evolved so as to provide us with as many calories as possible (long to our benefit) and, also, as many of the necessary but hard to produce nutrients. The alimentary canal is, evolutionarily speaking, a masterwork¹.

Not only are guts significant, they vary among species, much as do the leaves on trees or beaks on birds. When considering evolution’s great innovations, Darwin dallied among the beaks, but he might just as well have focused on the gut or even simply colons². A beak can pick something up, maybe crush it. Big deal. A colon can turn a bit of rotten fruit or leaf into energy and hence life. Science can replicate a beak; it is still working on making a good replica of a colon, much less replicating the great variety of colons and guts more generally found in nature. Carnivores such as lions have smooth stomachs big enough to hold the rump of a small antelope. In them, the muscles of prey are returned to the bits of protein out of which they are made. The stomachs of some herbivores on the other hand are dense with hair-like villi and, moving among them, the bacteria that aid in the breakdown of plant cell walls and their cellulose. The stomach of a cow is a kind of giant fermenter in which bacteria produce huge quantities of specific fatty acids the cow can easily use or store (You eat some of those fatty acids when you eat a cow). In other species, the stomach scarcely exists and fermentation takes place in a greatly enlarged large intestine.

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http://blogs.scientificamerican.com/guest-blog/2012/07/23/human-ancestors-were-nearly-all-vegetarians/?WT.mc_id=SA_facebook

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In the distant past, human beings died in their 20s and 30s. Women usually died during childbirth. Cheetahs used to eat our babies. Those were terrible times and I, for one, am glad we no longer have to live like that.

Put more succintly, fukc the past. Embrace the future.

[one...two...tree 2,762]

In the distant past, human beings died in their 20s and 30s. Women usually died during childbirth. Cheetahs used to eat our babies. Those were terrible times and I, for one, am glad we no longer have to live like that.

Put more succintly, fukc the past. Embrace the future.

Okay, just be ready for when your doctor refers you to a cardiologist, who tells you, you're gonna need open heart surgery if you want to live to see your grandchildren.

[^_^ 5,021]

Okay, just be ready for when your doctor refers you to a cardiologist, who tells you, you're gonna need open heart surgery if you want to live to see your grandchildren.

If I listen to you, a cheetah will eat my grandchildren and my daughter will die during childbirth. Screw your backwards-#### primitive vision, yo.