If you’ve ever dreamed of eating like the Flintstones, this diet is for you. The paleo diet’s name is derived from the fact that it consists of foods that people living during the Paleolithic era likely ate, according to Mayo Clinic. This regimen includes seeds, nuts, lean meats, fish, fruit and vegetables. Unfortunately, the diet cuts out dairy and grains, which, in moderate amounts, help sustain energy and bone health among other health benefits. The diet may also be prohibitively expensive, according to Mayo Clinic, because of its emphasis on grass-fed meats.