context: For more than 30 years, scientists have examined the relationship between food coloring and hyperactive behavior in children, but with mixed results. To date, no conclusive evidence has been found to show that food coloring causes ADHD. Some studies, though, have suggested an association between the two. Most likely, ADHD is caused by the combination of changes in brain structure, environmental factors, and heredity. A study of nearly 300 children by the United Kingdom's Food Standards Agency in 2007 showed that the consumption of foods containing dyes could increase hyperactive behavior in children. In the study of 3-, 8- and 9-year-olds, children were given three different types of beverages to drink. Then their behavior was evaluated by teachers and parents. One of the drink mixtures contained artificial food colorings, including: Sunset yellow ( E110) Carmoisine ( E122) Tartrazine ( E102) Ponceau 4 R ( E124) It also contained the preservative sodium benzoate. The second drink mixture included: Quinoline yellow ( E104) Allura red ( E129) Sunset yellow Carmoisine It also had sodium benzoate. The third drink mixture was a placebo and contained no additives. The researchers found that hyperactive behavior by the 8- and 9-year-olds increased with both the mixtures containing artificial coloring additives. The hyperactive behavior of 3-year-olds increased with the first beverage but not necessarily with the second. They concluded that the results show an adverse effect on behavior after consumption of the food dyes. Food coloring consists of chemicals used to add color to food. Food coloring (dye) is often added to processed foods, drinks, and condiments. They are used to maintain or improve the appearance of the food. Manufacturers usually add dye for the following reasons: To add color to colorless foods To enhance colors To avoid color loss due to environmental elements To provide consistency when there are variations in the coloring of the food The FDA regulates color additives to ensure that they are safe for human consumption. Regulation also helps ensure that foods with coloring are accurately labeled so that consumers know what they are eating. To determine the approval of an additive, the FDA studies the composition of it and how much is consumed and notes any health effects and safety factors that need to be observed. Once the food dye is approved, the FDA determines an appropriate level of use for that additive. The FDA only allows an additive to be approved if there is a reasonable certainty of no harm to consumers. There are two types of approved color additives - dyes and lakes. Dyes are water-soluble and usually come in the form of powders, granules, or liquids. Lakes are not water-soluble. They are found in products containing fats and oils. Some food colorings are synthetically produced. Examples of these color additives include FD& C Blue Nos. 1 and 2, FD& C Green No. 3, and FD& C Red No.40. Other food colorings come from pigments of vegetables, minerals, or animals. Examples of these natural additives include beta-carotene, grape skin extract, caramel color, and saffron. Processed sugars and carbohydrates may have an effect on a child's activity level. These sugars produce a rapid increase in blood glucose levels because they enter the bloodstream so quickly. A child may become more active due to an adrenaline rush produced by this blood sugar spike. Decreased activity in the child is sometimes noted as the adrenaline levels fall. However, there has been no proof to date that sugar actually causes ADHD.