First, play it safe. Talk with your doctor before taking any vitamins, minerals or natural dietary supplements. Because the Food and Drug Administration (FDA) regulates dietary supplements like foods--not medications--the ingredients in over-the-counter (OTC) products vary greatly. Some ingredients that are purported to help with weight loss include chitosan (blocks absorption of fats), chromium picolinate (enhances the action of insulin), conjugated lineleic acid (CLA), and green tea extract (curbs appetite). The concern is none of these are proven to be safe and effective. In fact, the Natural Medicines Comprehensive Database claims there is not enough evidence to rate these ingredients for weight loss. One supplement--green coffee extract--is rated as "possibly effective" by the Natural Medicines Comprehensive Database, but more research is recommended to determine safety. The most recommended way to lose weight is vitamin "L"--Lifestyle. Get more exercise. Eat plenty of fruits and vegetables. Manage your stress. Get plenty of sound sleep. Be happy. Vitamin "L" is shown to aid in weight loss and boosts longevity--and it's safe!