Food provides us with all the nutrients we need to live. However, certain components of food or their breakdown products can lead to symptoms such as headaches, digestive problems, skin rashes with itching or tiredness in some people. In fact, you may not tolerate certain foods. The reason for this can be a food intolerance: You lack the necessary enzymes to process substances such as lactose, fructose or histamine. Daosin is a food supplement with the enzyme DiAminOxidase (DAO). It supplements the body's own enzyme to break down histamine.