Biotin (also known as vitamin H) is part of the B complex group of vitamins.
It is found in brewer's yeast; cooked eggs; sardines; nuts (almonds, peanuts, pecans, walnuts) and nut butters; soybeans; other legumes (beans, blackeye peas); whole grains; cauliflower; bananas; and mushrooms.
It can also be taken as a nutritional supplement, either on its own or as part of a multivitamin.
Biotin helps to metabolise carbohydrates, fats, and amino acids, the building blocks of protein. Biotin is often recommended for strengthening hair and nails, and it's found in many cosmetic products for hair and skin
Some people believe that individuals with autism have significant metabolic abnormalities.
They also believe that some of those metabolic abnormalities can be addressed by consuming more foodstuffs containing biotin or by taking supplements of biotin (sometimes alongside supplements of other vitamins and minerals).