5-HTP is short for 5-Hydroxytryptophan, which is an amino acid. As a transitional component in tryptophan metabolism, 5-HTP is also a compound which in the metabolic pathway precedes the monoamine neurotransmitter serotonin. As a dietary supplement, 5-HTP is suggested for use as an antidepressant, sleeping aid, but also as an appetite suppressant. Vitamin B6 helps 5-HTP decarboxylate into serotonin, with assistance of a lyase enzyme, namely the aromatic L amino acid decarboxylase. The theory is that 5-HTP, when ingested as a supplement, leads to increased serotonin production. While mainly being used as an appetite suppressant in the body building community, it also improves cognitive abilities, but also endurance and stamina. While there are some concerns in use of 5-HTP and MAO inhibitors in combination, sensitive users report only positive effects, that is why it was included in Vanquish.

Hoodia Gordonii is widely thought of as an appetite suppressant; however, there have not been sufficient studies to support this theory.

Vitamin B6, also known as Pyridoxine, Vitamin B6 is an essential vitamin to aid in the formation of healthy red blood cells and supports more vital bodily functions than any other vitamin. A water-soluble vitamin, Vitamin B6 is needed to release energy from the food we eat. Vitamin B6 cannot be stored in the body, so it must be obtained daily from either food or supplements. Vitamin B6’s role as a coenzyme involved in the metabolism of carbohydrates, fats, and proteins is what makes it important for dieters. Vitamin B6 is also responsible for the manufacture of hormones, red blood cells, neurotransmitters, enzymes, and prostaglandins. Vitamin B6 is required for the production of seratonin, a brain neurotransmitter that controls mood, appetite, sleep patterns, and sensitivity to pain. For weight loss, dieters should include vitamin B6 to increase their metabolism while rounding out a healthy diet.