People who consume large amounts of sugar and refined carbohydrates are often low in several B vitamins, and improving B-vitamin intake may help address a range of health concerns. Evidence suggests a role for B vitamins in mood regulation, cardiovascular health, and pain modulation. A study published in Journal of Affective Disorders (Miyake Y, Sasaki S, et al., 2006) examined dietary B-vitamin intake and postpartum depression in 865 Japanese women who completed dietary questionnaires during pregnancy. Of these women, 121 developed postpartum depression between two and nine months after delivery. Women with higher dietary intake of riboflavin (vitamin B2) were less likely to develop postpartum depression than those with lower intake.
Adequate intake of B vitamins has also been linked to cardiovascular health. Research published in the Italian Heart Journal Supplement (2005; 6(1):1–16) reported an inverse relationship between atherosclerosis and deficiencies of folic acid, vitamin B12, and vitamin B6. These vitamins are required for the conversion of homocysteine, a potentially toxic amino acid associated with cardiovascular disease, into cysteine and taurine. Elevated homocysteine levels are considered a risk factor for atherosclerosis when B-vitamin status is inadequate. Supporting this, a report in the British Medical Journal (November 26, 2006) concluded that evidence from cohort studies, genetic research, and randomized controlled trials supports a modest protective effect of folic acid against heart disease through homocysteine reduction, noting that folic acid is inexpensive and generally safe.
B vitamins have also been studied for their effects on pain. Earlier research has shown that vitamins B1, B6, and B12 can reduce pain originating from nociceptors, the nerve endings that respond to tissue injury such as inflammation, burns, or trauma. Research presented to the American Physiological Society in April 2003 demonstrated that sensory neurons in the spinal cord activated by nociceptive stimuli were suppressed by certain B vitamins. More recent experimental work has shown that a combination of vitamins B1, B6, and B12 can reduce neuropathic pain caused by direct nerve injury. In animal studies, these vitamins reduced pain responses in a dose-dependent manner, as measured by withdrawal from heat stimulation, suggesting a potential role for B-vitamin support in nerve-related pain conditions.
