It has been three weeks and two days since the majority of Americans vowed to follow through with their New Year’s resolution and lose weight. Because over half of the American population is over-weight, this is a valid goal. When exercise and diet do not produce results, many people turn to diet supplements. Before anyone commits to a particular supplement it is best to educate yourself about the possible outcomes.The General Nutrition Center’s best-selling diet supplement is Xenadrine RFA-1. Elizabeth Refner, general manager of a GNC in North Houston, said Xenadrine aids dieters by suppressing appetite. “Xenadrine contains caffeine and Excedrin, which decreases appetite,” Refner said.According to an advertisement in “Max Sports and Fitness” magazine, Xenadrine increases weight loss 38.6 times more than diet and exercise alone. Although Xenadrine has not been evaluated by the Food and Drug Administration, clinical studies conducted at Eastern Michigan University states that compared to the placebo group, the Xenadrine group experienced 759 percent more weight loss without reducing their food intake.As convincing as ads can be, one question remainsdo diet supplements really work? Former Personal Trainer, Neil Maddox said he lost 30 pounds in two months on Xenadrine. “Through my training I saw results in just a month with and without working out,” he said. Although several products claim to be clinically tested, you have to find the product that works best for you, said Maddox. “If a person is going to exercise, the results obviously come faster. I would recommend running or some kind of cardio-exercise,” he said.As is the case with any drug, diet supplements can cause side effects. Because some supplements contain caffeine, Maddox suggest avoiding soft drinks and drinking a lot of water. Nervousness, increased heart rate, and mood swings are a few of the possible side effects, said Refner. It is best to take diet supplements before 3 p.m. to avoid sleeplessness. To prevent bad reactions to diet supplements, Refner tells her clients to take a multi-vitamin to fall back on. “Taking more protein depletes the caffeine,” said Refner. If side effects do occur, Refner said you should stop taking them and switch to a natural energizer. Diet supplements are not for everyone. “People with high blood pressure should not take Xenadrine,” said Refner.To learn more about Xenadrine visit their Web site at www.Xenadrine.com.