Caffeine- The bitter, white crystalline xanthine alkaloid caffeine is found in tea, coffee, soft drinks, chocolates, pain relievers, and a variety of over the counter medications. It is a psychoactive stimulant drug that causes increased alertness by stimulating the central nervous system. For the same reason, many people feel more energetic after consuming it. It even elevates the mood but these effects do not last for long. The effects of caffeine usually last for about five to six hours, though caffeine sensitivity varies from person to person. It has been found that people who consume lot of caffeine on a daily basis soon develop less sensitivity and may need to increase their intake to enjoy the same effect. Being a diuretic, a person consuming caffeine may have to urinate more often.

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.

Synthetic Guggulsterones is naturally found in the resin of the guggul plant, it is a plant sterol and the Latin name of the plant is Commiphora mukul. It is believed that in humans, an extract of the guggul plant functions as a farnesoid X receptor inhibitor, theoretically attributing to a diminished synthesis of cholesterol in the liver. It is a very popular nutritional supplement and exists in several synthetic variants which are popular with the body building communities. The most popular application is the one as a weight loss agent, but it has been observed that Synthetic Guggulsterones may also stimulate thyroid function directly. While there is a debate if synthetic or natural guggulsterones are to be preferred, the availability and price of Synthetic Guggulsterones is currently prevailing.

Yohimbe- Basically a tree bark, Yohimbe is rich in pharmacologically active chemicals. It is commonly found in products developed for body building and enhancing male performance. The use of Yohimbe causes serious side effects too that include renal failure, seizures and in very rare cases, even death. Individuals suffering from low blood pressure, heart disease, liver or kidney disease, and diabetes should refrain from using any kind of Yohimbe supplements. Taking larger doses of Yohimbe can cause weakness, stomach disorders, fatigue, and nervous stimulation followed by paralysis. It is therefore important to avoid self-medication. Sometimes, side effects may arise even if small amounts of this supplement are taken, especially for prolonged periods. If you are already taking drugs for treating some health condition, it is best to avoid this supplement.