There are two different types of gold leafs: genuine gold leafs and imitation gold leafs. The imitation gold leafs are made from a mixed alloy such as zinks, copper, and aluminium and thus are toxic and harmful. Therefore, they are not to be consumed by human.
The genuine gold leafs, although they are made from genuine gold (real gold) however, they are made for two different industries:
one is the industrial sector, usually used by gilders to gild furniture, picture frames and valuable objects. It is essential to know that they are made in a factory that lubricates their machines with industrial oil; therefore, they are too toxic and harmful for your body when consumed.
However, these genuine gold leaf manufacturers also produce genuine gold leaf for both the hospitality and cosmetics industries. However, these types of genuine gold leafs are made with strict hygiene standards, and all the machines are lubricated using vegetable oils instead of industrial oils.
Moreover, both the United States and the European Union authorised these types of genuine gold leaf for human consumption under food colouring # E175 and the genuine silver leaf under food colouring # E174). Hence they are called Edible Gold Leafs or Cosmetics Gold Leafs. The leafs are so thin that they will disintegrate in your mouth instantly.