What do depression, weight gain, insomnia, and anxiety all have in common? Research has shown that they are all linked to vital brain chemicals called neurotransmitters that affect everything from your mood to your appetite. One of the most important neurotransmitters is serotonin, which is created from a nutrient called 5-hydroxytryptophan - 5-HTP for short. In 5-HTP: Nature's Serotonin Solution, Dr. Ray Sahelian, one of the world's foremost experts on natural supplements, clearly explains what 5-HTP is and how it fits into the body's finely tuned serotonin system.If you have questions about how 5-HTP can improve both your physical and mental health, here is a single source you can turn to for reliable and comprehensive information.