Weight loss medications that are advertised as metabolic stimulants are said to speed up a person's metabolism therefore allowing them to burn more calories. One of the most popular metabolic stimulants used for weight loss that is now banned by the FDA was ephedra, also known as Ma-huang. While ephedra and other metabolic stimulants may cause a slight increase in metabolism especially when combined with caffeine, they can also cause insomnia, increase pulse rate, blood pressure, and anxiety.
Guarana, whose active ingredient is caffeine, is another popular herbal weight loss medication marketed as a metabolic stimulant. Guarana was also being combined with ephedra in other herbal weight loss pills before ephedra was banned by the FDA. Metabolic stimulants which contain a combination of caffeine and ephedra can put the person who is using them at risk for serious medical conditions such as a heart attack, stroke, and even death.
Many herbal weight loss medications are now claiming that pyruvate, an ingredient in many metabolic stimulants, will boost metabolism which will result in weight loss. There have been no credible studies conducted that have backed this claim. Anyone taking a metabolic stimulant containing pyruvate may want to note that large amounts of pyruvate may cause bloating and diarrhea.
Metabolic stimulants can be especially dangerous if the person taking a medication containing a metabolic stimulant already has high blood pressure, heart disease, or diabetes as they can cause an increase in heart rate and blood pressure. Many of the studies done on people taking metabolic stimulants for weight loss have shown little evidence for effectiveness other than for short-term weight loss.
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