Paleolithic diet
This evidence undermines a core premise of the paleolithic diet – that human digestion has remained essentially unchanged over time.
[13] On the other hand, following the diet can lead to nutritional deficiencies, such as an inadequate calcium intake, and side effects can include weakness, diarrhea, and headaches.
[14] Adrienne Rose Johnson writes that the idea that the primitive diet was superior to current dietary habits dates back to the 1890s with such writers as Emmet Densmore and John Harvey Kellogg.
Densmore proclaimed that "bread is the staff of death", while Kellogg supported a diet of starchy and grain-based foods in accord with "the ways and likings of our primitive ancestors".
[15] Arnold DeVries advocated an early version of the Paleolithic diet in his 1952 book, Primitive Man and His Food.
[16] In 1958, Richard Mackarness authored Eat Fat and Grow Slim, which proposed a low-carbohydrate "Stone Age" diet.
[18] In 1985 Stanley Boyd Eaton and Melvin Konner published a controversial article in the New England Journal of Medicine proposing that modern humans were biologically very similar to their primitive ancestors and so "genetically programmed" to consume pre-agricultural foods.
Eaton and Konner proposed a "discordance hypothesis" by which the mismatch between modern diet and human biology gave rise to lifestyle diseases, such as obesity and diabetes.
[19] The diet started to become popular in the 21st century, where it attracted a largely internet-based following using web sites, forums and social media.
This is not typical of more recently devised paleo diets; Loren Cordain's – probably the most popular – instead emphasizes animal products and avoidance of processed food.
For example, wild almonds produce potentially fatal levels of cyanide, but this trait has been bred out of domesticated varieties using artificial selection.
[35] Trying to devise an ideal diet by studying contemporary hunter-gatherers is difficult because of the great disparities that exist; for example, the animal-derived calorie percentage ranges from 25% for the Gwi people of southern Africa to 99% for the Alaskan Nunamiut.
[37] Researchers have proposed that cooked starches met the energy demands of an increasing brain size, based on variations in the copy number of genes encoding amylase.
[39] Some of the health claims made for it by its proponents, such as its ability to reverse diabetes and cure autoimmune diseases are exaggerated,[40] causing the diet to be controversial.
[44] There is some evidence that the diet can help in achieving weight loss, due to the increased satiety from the foods typically eaten.
[52] According to Cordain, before the agricultural revolution, hunter-gatherer diets rarely included grains, and obtaining milk from wild animals would have been "nearly impossible".
[67] As of 2019[update] the market for products with the word "Paleo" in their name was worth approximately $US500 million, with strong growth prospects despite pushback from the scientific community.
