Ma Huang (Ephedra)
This is an herb that stimulates the central nervous system. Claims for weight loss, increased energy, boosting performance and body building have been made.
A controlled study on weight loss showed that a group using ma huang combined with a low calorie diet had no greater weight loss than a control group using a placebo while following the same low calorie diet.
Because it is a stimulant, it increases blood pressure and heart rate. It can be hazardous to individuals with heart problems, diabetes, high blood pressure and thyroid conditions. When combined with caffeine-containing herbs (e.g., kola nut and guarana), it can be especially hazardous to these individuals. Side effects include insomnia, dizziness and tremor. The Food and Drug Administration (FDA) has received reports of more than 800 adverse reactions to ephedra, including stroke, heart attack and death. As a result, The FDA has proposed that products containing ephedra include warnings that 1) users should limit daily intake to 24 milligrams ephedra and 2) users should not take the product for longer than 7 days.