Dr. Oz promotes a great range of weight loss products, but this one has a longer history of safety, human use, and effects than most.
5HTP, which Dr. Oz promotes as a pre-meal supplement, http://www.doctoroz.com/episode/new-natural-appetite-suppressant, is a modified form of tryptophan.
Most people think of 5HTP, if they think of it at all, as a depression aid or a sleep aid. So fatigue and drowsiness are your biggest side effects to using this souped-up version of tryptophan (an amino acid and part of a complete protein).
Toxicity is very low, although the uninformed might site back to an outbreak of disease traced to contamination of tryptophan back in the eighties. (Reference and full side effect picture here). Since then, toxicity has only been theoretically considered when 5HTP is taken with SSRI (Prozac, Paxil, Zoloft, etc.) antidepressants.
So will 5HTP work as an appetite suppressant? A tiny, short-term study says yes. Twenty-seven volunteers experienced greater satiety using 5HTP.
What’s more interesting is that people dieting experience a drop in tryptophan levels, which may alter mood. So using tryptophan as an adjunct to dieting may increase your success. (Study here).
In contrast, patients experiencing cachexia, often a side-effect of cancer treatments, have a build up of tryptophan in their brains. Lowering their brain tryptophan levels can help them eat more. (Study here).
Usually Dr. Oz and I disagree on the level of evidence supporting a treatment. In this case, I would agree that tryptophan, not 5HTP, has enough evidence as a treatment with very low toxicity unless used in very large doses. The side effect of drowsiness would be the major concern, as would cross-reactions between tryptophan and other drugs.
Discuss a trial of tryptophan with your doctor before starting. It’s not a cure-all, but its side effect picture includes improved mood and sleep. Those are the kinds of side effects I wish we saw more of!