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NIH Report Indicates Alternative Diet Pill Safer and More Effective Than Ephedra
Washington DC, 26 December 2002

Every year, millions of Americans start dieting in hopes of losing weight they gained during the year. Many people might use controversial ephedra-based diet pills to help shed pounds. However, a new clinical study published by the National Institutes of Health indicates a relatively new ephedra-free diet agent, known as Xenadrine EFX, has similar metabolic-enhancing, caloric-burning capabilities as ephedra. Yet, unlike ephedra, Xenadrine EFX, which contains a specific green tea extract, has no history of "adverse events."

According to the NIH December report on "The Interaction of Physical Activity and Nutrition," medical researchers concluded that patients taking ephedra-free Xenadrine EFX increased caloric burn counts into the double digits.

Doctors say patients taking Xenadrine EFX were closely monitored and showed no signs of cardiac side effects, which are potential concerns of some people using ephedra.

The same research team also reports that it compared the efficacy of ephedra-free Xenadrine EFX to the efficacy of ephedra-based Dexatrim Natural and ephedra-based Metab-O-Lite diet pills. The conclusions, published in the "Journal of the American College of Nutrition," indicate patients burned significantly more calories taking ephedra-free Xenadrine EFX compared to when they took the two ephedra-based brands.

Chief Clinical Investigator Howard Schwartz, MD, Internal Medicine, South Miami Hospital, Director of Clinical Research at Miami Research Associates, Florida, site of the diet capsule clinical studies, says "The trials involved randomly selected patients whose resting metabolic rates were measured with an indirect calorimeter." Dr. Schwartz explains, "It is a device, recently approved for medical use by the U.S. Food and Drug Administration, which is proven to accurately determine how many calories a person is burning by gauging biological gases, respiratory rates and oxygen consumption levels." He adds, "Based on calculations, patients taking Xenadrine EFX daily would, on average, lose 25 pounds annually without altering current lifestyles."

Clinical Conclusions

In phase one of the clinical trial, patients only took Xenadrine EFX. Patients' metabolic rates were measured with an indirect calorimeter before they took the diet agent and every hour for five hours.

The study concluded that Xenadrine EFX increased metabolic rates by as much as 13.41 percent.

In phase two of the clinical trial, patients were given Xenadrine EFX on the first day. On day two they were given Dexatrim Natural. On Day three they were given Metab-O-Lite. Patients' metabolic rates were measured with an indirect calorimeter before and an hour after taking a pill.

The study concluded patients burned five percent more calories taking ephedra-free Xenadrine EFX compared to taking ephedra-based Dexatrim Natural. And, they burned 4.9 percent more calories taking ephedra-free Xenadrine EFX compared to taking ephedra-based Metab-O-Lite.

Patient Profile

"When I was taking Xenadrine EFX I didn't experience any side effects. I felt energized. I could feel my body temperature increase slightly and I noticed my appetite disappeared," says Lori Gross, 37, of Sunrise, FL, a clinical study participant.

Medical records show that while taking Xenadrine EFX Gross increased her metabolic burn rate from 1310 calories to 1550 calories per day. Gross says, "I did the math and that's a difference of 240 calories daily, which, over the course of a year, would add-up to a weight-loss of 25 pounds," She adds, "The doctor told me these calculations are based on the presumption that there are no significant changes in my current lifestyle."

Consumer Case Study

Thousands of Americans report losing significant weight, in some cases more than one hundred pounds, taking Xenadrine EFX as directed in conjunction with routine exercise and balanced diet.

"After the holidays one season, I made a resolution to lose weight," said 38 year old John Orrett, a global exporter of Miami, FL. "I had ballooned up to two hundred and ninety five pounds and I was huge," explained Orrett. He says his local health food store owner recommended Xenadrine EFX. "It made me feel motivated, it gave me energy, and it also helped me to suppress my appetite without side effects," said Orrett. "Within three to four months, I had lost 45 pounds, and within seven months I lost ninety five pounds," he said. Orrett said he is keeping the weight off by taking Xenadrine EFX as directed, eating nutritious meals, exercising regularly and even competing in triathlons and marathons.

Green Tea Extract

Green tea leaves grow on trees in Asia. After water, green tea is the second most-consumed beverage worldwide. According to a mountain of medical evidence, including a recent report from the University of Chicago, a specific green tea extract, known as epigallocatechin-3-gallate (EGCG), "has shown to modulate appetite, control obesity and reduce cholesterol" in lab subjects. Xenadrine EFX contains a precise EGCG compound, which is a powerful appetite suppressant that increases energy and accelerates the body's metabolism, enabling it to burn calories quickly.


Ephedra is an ancient Chinese medicinal root known as Ma Huang. There are isolated claims that ephedra causes heart palpitations and strokes. The U.S. Food and Drug Administration says there is no conclusive evidence that ephedra is dangerous.

Ephedra was recently banned as a diet product in Canada. It is banned by the International Olympic Committee, National Football League and National Collegiate Athletic Association.

In 2003, California's ephedra heart-safety labeling law goes into effect. Kansas, Nebraska and New York are considering similar laws. Sales of ephedra diet supplements are banned at all U.S. Army base stores worldwide. Attorneys in some states are filing lawsuits against a myriad of ephedra manufacturers contending the diet products posed health risks to their clients.

Xenadrine EFX

Cytodyne Technologies, Inc. of Manasquan, NJ is the maker of Xenadrine EFX and the complete Xenadrine diet supplement line. Xenadrine is America's number one selling brand of diet products, because they work. Xenadrine is available at Wal-Mart, GNC, thousands of chain and private drug stores nationwide and at hundreds of natural foods, nutrition and vitamin shops across North America.

Cytodyne says Xenadrine EFX is part of a new generation of thermogenic diet agents that it is now developing in response to consumers who want to take ephedra-free products and still lose weight fast. Pregnant or nursing women, children, people with cardiac, thyroid and other conditions should not take any diet product without consulting their physicians.


Cytodyne Technologies, Inc., manufacturer of Xenadrine EFX.end-of-story


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