Background: An association between low blood levels of folate [vitamin B(9)], vitamins B(6) and B(12) and a higher prevalence of depressive symptoms has been reported in several epidemiological studies.
The present study aimed to assess the association between folate, vitamins B(6) and B(12) intake and depression prevalence in the SUN cohort study [a tracking study of university graduates in Spain focused on identifying dietary determinants of various illnesses and conditions].
Methods: The study comprised a cross-sectional analysis of 9,670 participants.
A validated semi-quantitative food frequency questionnaire was used to ascertain vitamin intake. The association between the baseline intake of folate [B(9)], vitamins B(6) and B(12) categorized in quintiles and the prevalence of depression was assessed. The analyses were repeated after stratifying by smoking habits, alcohol intake, physical activity and personality traits.
Among women, odds ratios (OR) [95% confidence interval (CI)] for the third to fifth quintile for vitamin B(12) intake were 0.58 (0.41-0.84), 0.56 (0.38-0.82) and 0.68 (0.45-1.04), respectively. [Note: an OR of 1.0 would mean no difference in average risk between two groups being compared. So, for example, depression among these three higher-B(12) intake groups of women was 42%, 44%, and 32% less frequent.]
Among those men with a low level of anxiety and current smokers, a significant positive association between low folate intake and the prevalence of depression was found. The OR (95% CI) for the first quintile of intake was 2.85 (1.49-5.45) and 2.18 (1.08-4.38), respectively, compared to the upper quintiles of intake (Q2-Q5) considered as a group. [Average odds of depression in men with lower anxiety and men who smoke were 185% and 118% greater with lowest folate intake.]
• Low folate intake was associated with depression among currently smoking men and men with low anxiety levels.
• Low intake of vitamin B(12) was associated with depression among women.
• No significant associations were found for vitamin B(6) intake.
Source: Journal of Human Nutrition and Dietetics, Apr 2009;22(2):122-33. PMID: 19175490, by Sanchez-Villegas A, Doreste J, Schlatter J, Pla J, Bes-Rastrollo M, Martinez-Gonzalez MA. School of Health Sciences, Department of Clinical Sciences, University of Las Palmas de Gran Canaria, Las Palmas, Spain. [E-mail: firstname.lastname@example.org]