Researchers say that the addition of tubers and other starchy foods to ancient hearths helped contribute to human brain development. Credit Andrew Scrivani for The New York Times
The paleo diet has been all the rage amongst cross fitters and those wanting to lose weight. Thediet is based on the types of foods presumed (emphasis on this because there are no Pleistocene cookbooks to consult) to have been eaten by early humans, consisting chiefly of meat, fish, vegetables, and fruit, and excluding dairy or grain products and processed food. Which means no:
- Cereal grains (Amaranth, Barley, Brown rice, Buckwheat, Bulgur (cracked wheat), Farro, Flaxseed, Millet, Oats, Oatmeal, Muesli, and Quinoa to name a few)
- Legumes (all beans, peas, lentils, including peanuts)
- Dairy (Butter, Cheese, Cottage cheese, Milk, Yogurt)
- Refined sugar
- Starchy Vegetables (Potatoes, Sweet potatoes, Yucca, Squash, Yams, Beets — though they do make exceptions for athletes who need the carbohydrates for energy...)
- Processed foods
- Salt
- Refined vegetable oils
But recently, scientists have proposed that our hominin ancestors were able to fuel the evolution of our oversize brains by incorporating cooked starches into their diet.
Roughly seven million years ago, our ancestors split off from the apes. As far as scientists can tell, those so-called hominins ate a diet that included a lot of raw, fiber-rich plants.
After several million years, hominins started eating meat. The oldest clues to this shift are 3.3-million-year-old stone tools and 3.4-million-year-old mammal bones scarred with cut marks. The evidence suggests that hominins began by scavenging meat and marrow from dead animals.
At some point hominins began to cook meat, but exactly when they invented fire is a question that inspires a lot of debate. Humans were definitely making fires by 300,000 years ago, but some researchers claim to have found campfires dating back as far as 1.8 million years.
Cooked meat provided increased protein, fat and energy, helping hominins grow and thrive. But Mark G. Thomas, an evolutionary geneticist at University College London, and his colleagues argue that there was another important food sizzling on the ancient hearth: tubers and other starchy plants.
Our bodies convert starch into glucose, the body’s fuel. The process begins as soon as we start chewing: Saliva contains an enzyme called amylase, which begins to break down starchy foods
Another clue to the importance of carbohydrates, Dr. Thomas said, can be found in our DNA. Chimpanzees, our closest living relatives, have two copies of the amylase gene in their DNA. But humans have many extra copies — some people have as many as 18. More copies of the amylase gene means we make more of the enzyme and are able to derive more nutrients from starches, said Dr. Thomas.
Read the full article at NYTimes.com
