5-Hydroxytryptophan (5-HTP) is an amino acid that is the intermediate step between tryptophan and the important brain chemical serotonin. There is a massive amount of evidence that suggests that low serotonin levels are a common consequence of modern living. The lifestyle and dietary practices of many people living in this stress-filled era results in lowered levels of serotonin within the brain. As a result, many people are overweight, crave sugar and other carbohydrates, experience bouts of depression, get frequent headaches, and have vague muscle aches and pain. All of these maladies are correctable by raising brain serotonin levels. The primary therapeutic applications for 5-HTP are low serotonin states as listed in Table 1.