Citrus Aurantium is the Latin name for a citrus tree which grows bitter oranges. Traditionally being used by Chinese medicine and herbologists, the extract of the orange and the peel was used as a dietary supplement in concoctions with other herbs to suppress appetite. While other active ingredients of the citrus aurantium may contribute and even promote the effect, the main ingredient used in all weight loss products is synephrine, an alkaloid similar to ephedrine. It is a phenethylamine; it influences the alpha1 adrenergic receptor, constricting blood vessels, additionally increasing the heart rate and the blood pressure. In most cases the use of synephrine is paired with a diet and body building plan, where weight loss and muscle building is essential.

Green Tea Extract is a widely consumed beverage in the world. It is well known for its antioxidant properties. It is traditionally used to treat ailments such as headaches, poor digestion, and body aches. Green tea extract is rich in catechin which increases the level of cholecystokinin that suppresses that appetite, thus promoting weight loss. It also contains Pheophytins, chlorophylls, caffeine, and carotenoids that have anti-genotoxic and antioxidant properties. It also helps in thermogenesis and in the metabolism of fat, promoting weight loss. The EGCG content protects the body from free radical damages. It also blocks the carcinogens that may cause cancer and protects the body from digestive and respiratory infections. It also has anti-bacterial properties.

Hoodia Gordonii, which although popular, has no published randomized controlled trials in humans to show hoodia is safe or effective in pill form. One study published in the September 2004 issue of Brain Research found that injections of p57 (The Active ingredient in Raw, Fresh Cut Hoodia, not dried) into the appetite center of rat brains resulted in altered levels of ATP, an energy molecule that may affect hunger. The animals receiving the P57 injections also ate less than rats that received placebo injections. However, this was an animal study and INJECTIONS IN THE BRAIN are very different from oral consumption, so it cannot be used to show that oral hoodia can suppress appetite in humans. Hoodia Gordonii is a succulent (a cactus of the aloe family) found in the Kalahari desert of South Africa. Most Hoodia Gordonii products contain very little, if any of the active ingredient needed to suppress hunger. Real Hoodia is very rare and is even an endangered plant. Most importantly, Hoodia has only demonstrated any effect in fresh, raw pieces of the plant. The effectiveness of powdered Hoodia has yet to be shown and may actually increase hunger. It's main use is as a cheap alternative to the more expensive weight loss herbs, which are the only alternative left after the banning of ephedra. Most supplement manufacturers can not use the more expensive weight loss herbs because it will result in a product that would be too expensive to compete with other more popular inexpensive diet supplements.