In a recent post I mentioned the Paleo diet, and now I’ll examine that diet in some depth, in part because it’s defensible from a science perspective, and in part because it brings to mind our deep connection with the natural world and the importance of keeping that in mind when we make food choices.
Just looking at our bodies and thinking about how they function we can see that we have color vision that makes it possible for us to locate brightly colored ripe fruit hanging from a tree. We have the teeth of an herbivore—designed to bite and grind. Our single stomach rules out grass and woody plants as primary food sources. Fairly long intestines suggest the need to digest a lot of non-woody fiber—leaves, stems, roots. A gall bladder that stores bile for efficient digestion of fat means we’ve eaten animals for a long time. Our taste buds like sweet, meaty, and fatty. Put these all together and you come up with a likely ancestral diet of meat, eggs, fat, fruits, vegetables, and nuts—the foods of the Paleo diet.
Paleo is short for Paleolithic, the time period when humans were hunter-gatherers and used stone tools. They ate insects, nuts, berries–whatever they could find in nature–and took in more meat as their tools and hunting skills improved. This was way before the development of agriculture when humans started planting grains and domesticating animals for food. So the modern Paleo diet designed to replicate what our Paleo ancestors ate excludes all the grains—corn, wheat, rice, oats, barley–and leaves out dairy products, vegetable oils, sugar, and salt but includes large amounts of protein in the form of beef, buffalo, game animals, poultry, eggs, and seafood. This diet, say its advocates, makes sense because it is the one that we humans evolved with and to which our bodies are attuned.
The archeological records of the Paleo period show that early humans had strong bones and teeth and that once agriculture was introduced, they became smaller, weaker, more prone to disease. So advocates of the Paleo diet use these facts plus their own robust health to promote and defend their position. Among the promoters of the Paleo diet is Professor Loren Cordain of Colorado State University, whose website is a magnet for true believers. Mark Sisson is another advocate and speaks his truth at the website Mark’s Daily Apple.
One of the draws for the Paleo diet is the ease with which advocates say they have lost weight. Getting calories from fat rather than from carbs avoids the energy peaks and troughs that result from too much sugar in the blood. They do have their critics, though. For details go to the Wikipedia Paleo Diet post, where the controversies are discussed.