what is food grade diatomaceous earth

Food grade diatomaceous earth is a type of powder made from the sediment of fossilized algae found in bodies of water. It is largely made up of a chemical compound called silica, which is commonly found in nature as a component of everything from sand and rocks to plants and humans. Food grade diatomaceous earth is low in crystalline silica and considered safe for humans, containing 0.5-2% crystalline silica. It is used as an insecticide and an anti-caking agent in the agricultural and food industries, and is approved for use by the EPA, USDA, and FDA. It is also used as a filler or to prevent formation of lumps in foods, medicine, paints and plastics, and pet litter. Some farmers add it to their livestock and poultry feed to prevent the caking of feed. Food grade diatomaceous earth is often used as a supplement, and some users take it for its effects on nails, hair, and cholesterol levels, although there is very little scientific evidence to support these claims.