What can Merck's prescription drug Zetia do for you that niacin can't? Apparently, nothing at all. In fact, it could worsen your atherosclerosis.
A study published in the New England Journal of Medicine concluded that niacin, also known as vitamin B3, is better for reducing cholesterol and preventing heart disease than Merck & Co., Inc.'s prescription medication Zetia.
Researchers found that over a 14 month period niacin was significantly more effective at reducing artery plaque than ezetimibe, the active ingredient in Zetia. In addition, niacin was found more effective than Zetia at decreasing the number of heart attacks.
Zetia is a medication used in conjunction with statins to try to further lower levels of the so-called bad LDL cholesterol in the blood. It claims to work by blocking the absorption of cholesterol in the digestive track. Annual sales of the drug in 2010 were $2 billion.
The study was halted early because the niacin group was doing better. In fact, the researchers concluded that the more LDL cholesterol was reduced in the Zetia group, the greater was the progression of their atherosclerosis. In addition, there were significantly more major cardiovascular events among patients using Zetia than among those in the niacin group.
The lead author of the study questioned whether Zetia was effective at all and concluded that "prudent clinical practice currently favors the avoidance of ezetimibe" until further clinical studies are conducted.
What is niacin?
Niacin is a water soluble B vitamin also known as "nicotinic acid" used by the body to convert carbohydrates, fats and protein into energy. It also contributes to keeping the nervous system, digestive system, skin, hair and eyes healthy.
Niacin has been used for over 50 years as an effective method for raising the levels of good HDL cholesterol in the blood and is also known to help reduce bad LDL cholesterol and triglycerides.
What foods contain niacin?
Niacin is widely available in the food supply. The principal food sources of niacin include:
• Dairy products
• Lean meats
• Nutritional yeast
• Wheat germ
• Whole grains
Most people get sufficient niacin in their daily diets. Minimum requirements are 14-16 milligrams per day to prevent pellagra, a disease characterized by diarrhea, dementia and dermatitis. If left untreated it can lead to death.
Pellagra was widespread when people ate a diet heavy in corn rather than other whole grains since corn is very low in niacin. Native Americans traditionally cooked corn with lime because lime improves niacin absorption in the body, thus preventing the disease.
The optimum daily amount of niacin has not been set but a typical multi-vitamin will contain 20 milligrams, and many B complex vitamin supplements will contain as much as 200 milligrams.
Niacin for cholesterol control
The idea that there are "bad" and "good" blood lipids that contribute to heart disease is known as the "lipid hypothesis," or "cholesterol myth." The hypothesis is subject to much criticism and has been challenged often.
Nevertheless, most doctors continue to use cholesterol numbers to determine treatment. For treating high cholesterol, prescription doses of niacin are typically used only under a doctor's supervision.
Consult with your doctor and dietitian or nutritionist if you have been diagnosed with high cholesterol and are concerned about the side effects and efficiency of statin drugs and ezetimibe, since niacin may be a better alternative.