What happened? A new study reports that the popular nutritional supplement policosanol does not reduce cholesterol levels.

Previous studies suggested that policosanol reduced total cholesterol and low-density lipoprotein (LDL), or "bad," cholesterol. Policosanol was also reported to boost high-density lipoprotein (HDL), or "good," cholesterol. Most of these studies were supported by a single research group. The latest study — which included 143 participants from multiple sites and a placebo control group — found no distinct link between policosanol and changes in cholesterol levels.

Policosanol is sold in oral supplements and products such as One-A-Day Cholesterol Plus vitamins.

What does this mean to you? Few natural products have been proved to reduce cholesterol. If you're thinking about taking a cholesterol-lowering supplement, check with your doctor. And remember the importance of healthy lifestyle choices. Eat healthy foods, exercise regularly and avoid smoking. If your doctor prescribes medication to reduce your cholesterol, take it as directed while you continue to focus on a healthy lifestyle.