The Paleolithic diet (or Paleo diet), also referred to as the caveman diet, Stone Age diet, and hunter-gatherer diet, is a modern nutritional plan based on the presumed ancient diet of wild plants and animals of ancestral humans during the Paleolithic era (a period of about 2.5 million years duration that ended around 10,000 years ago with the development of agriculture). The diet consists mainly of fish, grass-fed pasture raised meats, vegetables, fruit, fungi, roots, and nuts, and excludes grains, legumes, dairy products, salt, refined sugar, and processed oils.