The Dr. Hay iet (also called the Hay Diet) is a nutrition method developed by the New York physician William Howard Hay in the 1920s. It claims to work by separating out food groups into those which are "alkaline, acidic and neutral". Acid foods are not combined with the alkaline ones. "Acid" foods are protein rich, meat, fish, dairy, etc., and "alkaline" the carbohydrate-rich starch foods like rice, grains and potatoes.