Question: I've been reading a lot lately about the dietary supplement, Xenadrine. What's your opinion on it? I'm 5'8'', about 175 lbs, and looking to lose the extra weight and tone up. I currently work out about 4 times a week, mostly on the ellipticals and treadmills for about 45 minutes - 1 hr. Is Xenadrine something that could improve my workouts and weight loss?

Answer: Xenadrine is an herbal weight loss formula that has been touted as "The most sophisticated and effective fat-burning compound available." Xenadrine contains ephedra, also known as Ma Huang, which is a source of ephedrine. Ephedrine is a bronchodilator and a potent stimulant. When combined with caffeine, which amplifies its effects, ephedrine has been proven in published studies to reduce appetite, spare lean body mass, increase fat burning and increase metabolism through a process called thermogenesis. Adding aspirin to the combination (ECA stack) gives it even more punch, although the ephedrine-caffeine (EC) combo does work by itself.

Ephedrine may sound like a miracle drug, but side effects can include increased blood pressure, jitteriness/speediness, insomnia, increased heart rate, heart palpitations, muscle tremors, nervousness, irritability and dry mouth. A powerful central nervous system stimulant with properties similar to amphetamines, the EC combo essentially puts your body into "fight or flight" stress mode - the exact opposite of relaxation. Prolonged or excessive use can exhaust your adrenal glands and get you "wired out." In Xenadrine, the amino acid L-Tryosine has been added to the formula because it provides adrenal and thyroid support and helps to reduce the jitteriness caused by the EC combo.

Herbal products such as Xenadrine are not the same things as pure ephedrine and caffeine. Ephedrine is an over the counter drug, ephedra (Ma Huang) is the plant it is derived from. Ephedra has been used in Chinese medicine for over 5000 years for asthma and respiratory problems. Guarana is the herbal source of caffeine (other formulas use kola nut or green tea.) Willow bark is the herbal analog of aspirin. Most herbal formulas fall far short of the 300 mg. of aspirin that was used in the ECA research (although the aspirin is the least important component of the stack). Ads for Xenadrine often quote the original research such as the studies published in the International Journal of Obesity in the early 1990's. However, these studies were conducted not with the plants but with the pure drug in the exact dose of 20 mg of ephedrine and 200 mg of caffeine.

There is a big difference between the whole plant and the herbal extract and there is an even bigger difference between the extract and the pure drug itself. The herbal products are not nearly as strong as the pure ECA stack. Ephedrine is the alkaloid (the active ingredient) in ephedra. The amount of active ingredient in the plant can vary greatly from one brand to the next. As much as 98% of an herb could be completely inert and only 2% active. Therefore there may not be a large enough dosage of the active ingredient to get any beneficial effect. To save money, some unscrupulous companies may use herbal extracts that contain very little of the active ingredient. The only way to know the potency of the products is if the alkaloid content is listed on the bottle as a "standardized extract." And even then, we're taking the company's word for it that what's in the bottle meets the label claims. Xenadrine contains 335 mg of Ma Huang, standardized to 6%, which equals the correct dose of 20 mgs. of ephedrine. It also contains 910 mg of Guarana, which standardized to 22%, yields the requisite 200 mgs. of caffeine.

As far as long-term safety goes, ephedrine has an outstanding track record when compared to other over the counter products such as aspirin, sleep aids and acetaminophen (despite a few horror stories to the contrary.) Most health problems caused by ephedra or ephedrine resulted from taking massive doses or they were taken by people with pre-existing health problems. Ephedra products should not be used if you are pregnant, if you are on MOA inhibitors, or if you have high blood pressure, cardiovascular disease, thyroid disease, diabetes, glaucoma, an enlarged prostate, or gastric ulcers. You should also stay away from these products if you are sensitive to stimulants or if you suffer from insomnia. Most people tolerate herbal weight loss products well, but a few get really "wired." Usually the jitteriness that accompanies using ephedrine recedes after one or two weeks as tolerance develops. If you are an athlete and you have to take a drug test, also keep in mind that ephedrine is banned by the International Olympic Committee.

My advice on how to take Xenadrine and other herbal "fat-burning" products is to use them only for a few months at a time during a fat-reducing program followed by at least two or three weeks off. Using Xenadrine or the ECA stack in a cyclical fashion will help prevent side effects associated with long term use and will prevent you from becoming habituated to the effects. If you stay on it too long, your body tends to develop a tolerance and the effects begin to diminish. For this reason, some people use it only every other day. Once you reach your desired weight and body fat level, you won't need it anymore, although you can continue to use it occasionally as a stimulant before tough workouts. Definitely take it about 30 minutes prior to your workout, as it will help boost energy and workout intensity dramatically. Avoid taking it late in the day as it can cause insomnia. Under no circumstances should you ever take more than the recommended dosage of 20mg ephedrine and 200 mg caffeine two to three times per day (twice a day seems to do the trick - Xenadrine recommends two capsules twice a day)

The bottom line is that herbal "thermogenic" products work but they don't work miracles. They are effective pre-workout stimulants and mild fat burners. Xenadrine is one of the better brands because the product was formulated based on the published research and the herbal extracts are standardized to the correct potency. Herbal fat burners don't work without a proper training and nutrition program and they are not a substitute for exercise. The only proven way to lose body fat is by reducing calories and increasing activity. Make sure your diet is in order first because no herbal product will help you if you have a poor diet. Once you're eating nutritiously, restricting your caloric intake, and working out aerobically and with weights, then Xenadrine (or the ECA stack) might give you that extra boost that you're looking for. Ask Tom a Question

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