Eating raw is arguably the oldest form of human subsistence. Some native groups such as Inuits still largely eat a raw diet. Chemistry studies by Finnish researcher Arturri Virtanen in the first half of the 20th century showed that chewing raw food produced enzymes that aided digestion. That and other enzyme studies as well as an experiment that compared the health of cats on a raw food diet to those eating cooked foods – the raw food cats were found to be healthier -- inspired a small group of vegetarians to speculate on the health benefits of humans eating raw.

Considered an extreme form vegetarianism, raw food came into its own in the 1980s with a series of books that advocated raw foods for health and longevity. It entered the mainstream in the 1990s with the emergence of fine dining restaurants that specialized in raw such as the now-shuttered but much-celebrated Roxanne’s in Larkspur, California. Now several raw foods diet cookbooks vie for attention on the bookshelves and upscale chefs across the country are putting raw dishes on their otherwise cooked menus.