Natural Remedies for Losing Weight ֠5-hydroxytryptophan (5-HTP) Another natural remedy for losing weight that has raised a few eyebrows is a substance called 5-hydroxytryptophan (5-HTP). In fact, its been called into question for its safety record. 5-HTP actually replaced tryptophan supplements banned due to its link to a rare and potentially deadly blood disorder. Also, there has been a difference of opinion on whether or not it is actually a viable substance for achieving weight loss. Now, having said that, 5-HTP is found in some over-the-counter natural remedies for losing weight.