Fats are made of glycerol and fatty acids. These both contain just carbon, hydrogen and oxygen. Testing for fats[edit | edit source] Why we need fats[edit | edit source] We need them to insulate our bodies and to protect our organs. Fats can also be used to for energy. Retrieved from "https://gcse.wikia.org/wiki/Fats?oldid=4398" Categories: Biology Add category Cancel Save Community content is available under CC-BY-SA unless otherwise noted.