The body converts 5-HTP into serotonin, a very important brain chemical. As a result, taking 5-HTP can increase serotonin levels, which theoretically may help with a variety of conditions, especially mood disorders (such as depression). In addition to affecting mood, serotonin has several other actions in the body, which may be how 5-HTP works for other conditions. There is some speculation that increased levels of serotonin in the brain may decrease food cravings, which may be why people use 5-HTP for weight loss.
Many prescription
antidepressants work by increasing the level of serotonin in the body, so it seems reasonable to predict that 5-HTP may have actions similar to antidepressants. Prescription antidepressants are often effective for all of the conditions listed above, which is probably why people try 5-HTP for these conditions.