Paleo foods include grass-produced meats, fresh fruits, eggs, fresh vegetables and healthful oils, such as olive oil and flaxseed oil. The paleo diet focuses on foods that were likely eaten by the prehistoric ancestors of humans.
Foods avoided by those on the paleo diet include potatoes, cereal grains, refined sugar, salt and processed foods.
Dr. Loren Cordain, considered the creator of the paleo diet, has written several books about it, including "The Paleo Diet," "The Paleo Diet Cookbook," "The Paleo Diet for Athletes" and "The Paleo Answer." The books provide details for food choices compatible with the diet. Dr. Cordain claims the diet causes fat loss and reduces the likelihood of certain diseases, such as heart disease and cancer.
The plan allows dieters to have up to three cheat meals per week when starting. While dieters do not have to exercise, it's recommended for health benefits. The plan doesn't require in-person meetings, but there are many online groups related to the diet, as of June 2015.
Critics of the paleo diet argue that it denies the benefits of modern human eating habits, that it assumes modern humans are biologically identical to prehistoric humans and that it's based on one section of human history. Additionally, the plan may present an inaccurate view of past humans, as certain aspects of prehistoric humans' eating habits remain unclear.