However, in 1988 a Japanese company introduced into America L-tryptophan, and some two million Americans bought it at health food stores. It was made using a newly generated bacterium that was very efficient and that made a lot of tryptophan. So that really taught me something. It was first marketed in Europe and France about 10 years ago and subsequently sold in 65 countries outside the United States, where it finally won FDA approval last spring. Redux had its roots in research that Wurtman and a student were conducting in 1971 on tryptophan, an amino acid that is converted into serotonin in nerve cells in the brain.
Carbohydrates increase serotonin, which acts as an antidepressant.
A few years later, we discovered that the brain uses this change in serotonin levels as a signal to determine what you are eating. Dr. Judith Wurtman was at the same time was studying carbohydrate craving in relation to obesity. Then we went back to our earlier discovery that carbohydrates increase brain serotonin. We came up with a hypothesis that the reason these people were overeating these snacks is because they didn't feel good. We tested this in large numbers of patients and found it to be the case.