"Paleo" stands for the Paleolithic era, or the Stone Age. It began about 2.5 million years ago and ended around the time of the last Ice Age, about 10,000 years ago. At that point, the Paleolithic era turned into the Neolithic era, which is when humans started to settle down and develop agrarian techniques. That meant there were more farmers and fewer hunter-gatherers.
The Paleo, or Paleolithic, diet is a fad diet based upon the perceived foods of the Paleolithic era. The dieter is urged to eat more like a hunter/gatherer rather than a farmer. The premise is human beings have not yet evolved past the Paleolithic era biologically and should not be eating the neolithic-like agriculturally produced foods. Proponents further claim that foods the Paleolithic hunter-gathers ate was the reason they didn't suffer from chronic diseases of aging such as diabetes, arthritis, heart disease and cancer (as opposed to dying before they got old).
The Paleolithic diet is heavy on protein, mostly from animal sources. To adhere to this diet, you'll need to consume things you'd hunt for or gather in the wild. That's almost impossible to do in our modern age, so you'll be following a modified version: eat plenty of animal flesh, fish, and seafood. Round out the diet with eggs, nuts, seeds, fruits and vegetables. In addition, you'll have to avoid all dairy products, all cereal grains (such as wheat, rice, quinoa and oats), tubers (potatoes and sweet potatoes), legumes (beans and peanuts), salt, sugar, and all processed foods.
What Did Paleolithic People Eat?
That's a good question, and it appears that archaeologists aren't 100 percent certain what foods humans ate back then. There is evidence of butchered animal bones, so that leads to meat taking the center stage of a Paleolithic diet, and there's evidence for fishing along shorelines.
But what about plant-based foods? Why are grains so tabu? Since plant matter disappears, it's harder to know how much or which plants were gathered and eaten. It's unlikely, however, that Paleolithic people avoided wild grains. In fact, some archaeological studies indicate that Paleolithic humans might have increased their intake of wild cereal grains and reduced their meat consumption in the late Paleolithic era, as humans got closer to the Neolithic agricultural age.
Why Is Farmed Food Bad?
That's also a good question. It isn't. At some point, Paleolithic humans decided to plant some of those seeds they had gathered. They also began to capture and domesticate some of the animals. The growth of agriculture was a key to the growth of the human species. The more people you have, the more efficient you need to become at feeding everybody. Otherwise, somebody's going to starve to death.
Paleo proponents claim grains are bad because pos-Paleolithic humans didn't evolve to eat them properly, and the starchy foods probably increased tooth decay. Another Paleo claim is that grains and dairy products (from domesticated animals) have led to the increase of chronic diseases that we see now, 10,000 years later. There is a kernel of truth to that, because it appears excessive intake of calories (often from processed foods that usually include grains or dairy products somewhere in the ingredient list) promotes obesity and the diseases that come with it. However, I think it's over-reaching to state grains and dairy products are all bad. Plus, there's plenty of research evidence to indicate both dairy products and grains have dietary benefits.
What If I Want To Follow the Paleo Diet?
The diet has a couple of good points in that it promotes eating whole foods and increasing your intake of fruits and vegetables. The diet also cuts out sugars and heavily processed foods. These are all good things that a lot of fad diets promote, so from that viewpoint, I don't see how it's any more beneficial than any other fad diet. Some small research studies indicate a Paleo diet might be beneficial for diabetics, but more research is needed to know if it's any more beneficial than a typical easier-to-follow diabetic diet.
On the negative side, the Paleo diet excludes a lot of healthful foods, which seems unnecessary (and makes it difficult to follow for a long term). There's a strong possibility of becoming deficient in calcium, and you won't get enough vitamin D (unless you get enough sun exposure). Paleo dieters tend to eat more protein and fat than what is considered healthy by the United States Department of Agriculture and the Academy of Nutrition and Dietetics.
Academy of Nutrition and Dietetics. "Back To Basics for Healthy Weight Loss." Accessed February 4, 2013. http://www.eatright.org/Public/content.aspx?id=6847#.UQ_ia1rjmPU.
Academy of Nutrition and Dietetics. "Should We Eat Like Our Caveman Ancestors?" Accessed February 4, 2013. http://www.eatright.org/Public/content.aspx?id=6442471551#.UQ_iMVrjmPU.
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