Vitamins - Dietary Health Benefits

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Protection Against Heart Disease

Vitamins and Heart Protection.

• Antioxidant Vitamins A, C, and E. Deficiencies in vitamins A, C, E, and beta carotene have been linked to heart disease. All of these nutrients have antioxidant effects and other properties that should benefit the heart. However, several studies have found no reductions in heart disease in people who have taken antioxidant vitamins. In fact, a 2005 study has found that taking high doses of vitamin E is associated with an increased risk of heart failure. In 2003, the US Preventive Service Task Force concluded that, to date, evidence is insufficient to confirm or refute the benefits of supplements of any of these vitamins in protecting against heart disease. It is important to note, in addition, that each of these supplements may even be harmful to the heart in high doses.
• Folate and B12 Vitamins. Deficiencies in the B vitamins folate (known also as folic acid) and B12 have been associated with elevated blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. Some studies in 2002, suggest that any risk posed by homocysteine or benefits from folic acid for heart disease are at most modest. One study, however, reported lower failure rates after heart surgery in patients who took folic acid and vitamins B12 and B6. And a major 2002 study suggested that lowering homocysteine levels with folic acid would reduce the risk for heart disease by 16% and stroke by 24%. More evidence is needed to determine whether homocysteine plays a causal role in cardiovascular disease and whether the B vitamins are protective. Folate improves blood flow through the arteries, which may be important for the heart, regardless of its effect on homocysteine.
• Niacin. Niacin (vitamin B3) is used for lowering unhealthy cholesterol levels. Although vitamin B3 is available over the counter, it can have significant side effects. A physician should prescribe niacin in order to ensure its safety and effectiveness. [For more information, see In-Depth Report #23, Cholesterol.]