They're the sparks that ignite the body's energy stores, fueling metabolism and a host of vital functions. Depression relief, heart health, birth defect prevention—the B vitamins have it covered. It's not all good news, however, when it comes to this vitamin family of eight. Research suggests that deficiencies of this micronutrient may be more widespread than one might think.
Vitamin B acts as a coenzyme in the body, helping other enzymes to produce chemical reactions. All of the Bs appear to work synergistically, which is why a deficiency in one B usually indicates a deficiency in another. According to Marilyn Sterling, a registered dietitian at Sterling Associates in Trinidad, California, vitamin B6 and folic acid deficiencies occur frequently in the general population, the consequence of a diet poor in fruits, vegetables, legumes, and whole grains. A steady intake of refined flour, sugar, coffee, and alcohol can compound the problem, says Elson Hass, M.D., who practices in San Rafael, California, as these deplete B vitamins in the body. Alternately, while vegans might eat their fair share of healthy plant foods, they can be deficient in B12, which is found mainly in animal products—unless they take supplements.
And if that isn't enough incentive, women have particular reason to take steps against a B deficiency. A study published in the Journal of the American Medical Association reports that perhaps half of all neural tube defects, which include spina bifida and anencephaly, could be prevented if mothers (and women trying to conceive) consumed enough folic acid, or B9—a recommended 400mcg for this population. Those trying not to get pregnant, on the other hand, also need to take heed. Birth control pills can depress absorption of folic acid, B2, B6, and B12.
In addition to its role in nervous system function, new research has linked vitamin B to the prevention of heart disease and strokes. High levels of homocysteine, a compound used in amino acid conversion, is believed to be toxic and can alter the integrity of the artery walls, allowing plaque build-up. Folic acid, B12, and B6 have been shown to reduce the amount of homocysteine in the body when taken in unison.
Those who suffer from depression, anxiety, and mood swings may also find relief through B supplementation. Studies have shown that deficiencies in vitamin B can result in depression and that increasing intake can significantly reduce anxiety and help ease the blues.
In addition to food sources, you might try a supplement to ensure against deficiencies. When shopping for a B complex, Sterling recommends "a supplement in which all the B vitamins are present at about the same percent of RDA."