Constipation, diarrhea, or upset stomach may occur. These effects are usually temporary and may disappear as your body adjusts to this medication.

These vitamins are essential for a fully functioning metabolism. The main function of the B vitamins is to help your body metabolize carbohydrates, proteins, and fats, and to use the stored energy in food. Thiamine (B-1), for example, helps the body cells convert carbohydrates into energy.

The One A Day Multivitamin is an excellent source of nutrients that support metabolism, as well as immune and bone health.

the United States Many people wonder, “Are One a Day vitamins made in China?” In reality, the supplements brand is owned by Bayer Corporation, which has its headquarters in Germany. However, despite the location of the Bayer headquarters, the actual manufacturing of One-a-Day vitamins happens in the United States.

Despite the hype, supplements that are promoted as fat busters and metabolism boosters rarely have a significant effect on weight loss. If you want to shed excess pounds, cutting calories from your diet and exercising more regularly are probably your best bets.

Don't look to dietary supplements for help in burning calories or losing weight. Products that claim to speed up metabolism usually don't live up to their claims. Some may cause bad side effects. The U.S. Food and Drug Administration doesn't ask for proof that dietary supplements are safe or that they work.

Fat burners have many strikes against them. They aren't regulated, contain questionable ingredients and aren't likely to give you a sculpted shape. And some of them are downright dangerous. If you're considering these supplements, talk it over with your doctor or a pharmacist first.

A slow metabolism burns fewer calories, which means more get stored as fat in the body; that's why some people have difficulty losing weight by just cutting calories. A fast metabolism burns calories at a quicker rate, which explains why some people can eat a lot and not gain extra pounds.

More Information: The FDA does not approve dietary supplements for any purpose. Products that have claims to treat, diagnose, prevent, or cure diseases are generally subject to regulation as drugs. Bottom Line: If a supplement promises a cure or quick fix for a health problem, it is probably too good to be true.

The Bottom Line. It is important to remember that a multivitamin cannot in any way replace a healthful well-balanced diet. The main purpose of a multivitamin is to fill in nutritional gaps, and provides only a hint of the vast array of healthful nutrients and chemicals naturally found in food.

Effectiveness: One study in 3,411 people compared the effectiveness of several medications for obesity and found that people taking phentermine lost the highest percentage of body weight over 12 weeks. Those taking phentermine lost an average of 8.3 lb (3.75 kg) throughout the study.

Drugs can be a help in obesity treatment, but they are not a magic bullet that allows us to shed pounds effortlessly. A small minority of people do find them a helpful adjunct to a diet and exercise program.