Dr. Benjamin F. Feingold, once a Professor of Allergy in San Francisco, claimed that hyperactivity was increasing in proportion to the level of food additives and proposed a specific diet believing that it would help 50% of hyperactive children.
The Feingold diet excluded cola drinks, chocolate, preservatives and flavor additives, as well as salicylates that occur naturally in fruit such as tomatoes, strawberries, pineapples and oranges. However pineapple juice was suggested as a "safe" drink.
The effectiveness of the Feingold diet has been heavily disputed. Most controlled double-blind studies have shown that only 5% of children diagnosed with ADHD benefited from the diet.
The question of whether or not diet and ADHD are linked in children has been debated for decades. However, carefully controlled studies of additives and sugar have not found any correlation between diet and ADHD