Artificial colorings and preservatives in food and drink are thought to contribute to hyperactivity in pre-school children, and while many still contest this issue, a recent study in the UK found that the proportion of hyperactive children was halved when additives were removed from their diets. Many additives—such as preservatives, artificial sweeteners, colorings and flavorings, MSG, hydrogenated fat, and phosphoric acid—are prohibited in organic food production.