What is the potential importance of taking B-vitamins?

Some of the B-vitamins, including thiamine (vitamin B1), riboflavin (vitamin B2), and niacin (vitamin B3), may be adequately supplied by the typical Western diet, because they are added to white flour products and other foods that have been depleted of those vitamins. Another vitamin, biotin, is produced by intestinal bacteria in amounts that, along with typical dietary biotin intake, provide enough of this vitamin to prevent deficiency in healthy people. Pantothenic acid (vitamin B5), on the other hand, appears to be in short supply in the typical diet. In one study, 49% of a group of male and female adolescents were consuming less-than-adequate amounts of pantothenic acid in their diet.No research has investigated whether supplements of these B-vitamins prevent disease.

Vitamin B6 (pyridoxine) deficiency, at least in a mild form, may exist in 10 to 25% of people living in Western societies, and may be most common in the elderly. The possible role of vitamin B6 in the prevention of heart disease by helping to regulate blood homocysteine levels is discussed below. No other research on preventive effects of vitamin B6 supplementation has been done.