Written by Tatjana Djakovic, Staff Writer. This study demonstrated that higher total intakes of both vitamin B-6 (10 mg) and vitamin B-12 (10 mcg) were associated with a 2% lower risk of developing symptoms of depression per year.
People often assume that depression is just a normal process that accompanies aging, when in fact it is a serious illness that affects 7% to 49% of the elderly in the general population. Depression in the elderly is particularly difficult to diagnose due to complications brought about by other medical illness. (2) Older Americans are at a higher risk of committing suicide than any other age group. (3) Furthermore, research has shown that elderly depressed patients have approximately 50% higher total health care costs than their non-depressed peers. (4)
Numerous studies have analyzed the correlation between B vitamins and depression. However, only a few provided evidence from population-based studies of older adults. Biochemically, some of the B vitamins are necessary for the metabolism of homocysteine. If there is an insufficient level of vitamin B-12, B-6 or folate present, homocysteine cannot make methionine (amino acid obtained from diet), resulting in a buildup of homocysteine in the blood. (1) Homocysteine is an amino acid normally present in blood; however, elevated levels of homocysteine may contribute to depression, dementia and loss of brain function in the elderly
The objective of a recent study was to examine whether dietary intakes of vitamin B-6, folate and vitamin B-12 contributed to decreased symptoms of depression. The study included 3503 elderly adults at least 65 years old from the Chicago Health and Aging project and was conducted over an average of 7.2 years. The dietary assessment was conducted by having the participants complete a food frequency questionnaire based on their consumption of 139 different foods as well as vitamin supplements. The assessment of depressive symptoms was based on a 10-item version of the Center for Epidemiologic Studies Depression scale (CES-D). A score of 4 or higher was considered to be a reasonable indicator of an older adult with major depression. (4)
Socio-demographic variables, which included age, sex, race, education, and income, were used to group individuals and assess the vitamin B intakes on each group of individuals. Furthermore, the study controlled for antidepressant use, smoking, alcohol use, cognitive function, physical disability, and medical conditions, in order to test if any of the conditions, played a role in affecting the intake of B vitamins.
The data showed noticeable trends of participants with more education and higher income, as well as participants with higher cognitive function, having higher intakes of each of the nutrients. Also, the modeling results for total intakes show that higher intakes of both vitamin B-6 and vitamin B-12 were predicative of decreased depressive symptoms over time (P values ranged from 0.01 to 0.07). The P values indicate that the decrease in depression symptoms occurring by chance alone is only 1% to 7%. Furthermore, the low P values represent a strong relationship between intake of vitamins B-6, B-12 and decreased depression symptoms. However, folate was not associated with a decrease in depressive symptoms over time (P values ranged from 0.61 to 0.91), which may be due to mandatory folic acid fortification of the grain supply by US Food and Drug Administration in 1998. Furthermore, the odds ratios of groups with additional variables such as alcohol intake, smoking, and cognitive function remained virtually unchanged for both vitamin B-6 and vitamin B-12.
This study has demonstrated that higher total intakes of both vitamin B-6 and vitamin B-12 were associated with decreased development of depressive symptoms. In fact, each additional 10 mg of vitamin B-6 and 10 mcg of vitamin B-12 were associated with 2% lower odds of development of depressive symptoms per year. (4)
Source: Skarupski, Kimberly A., et al. “Longitudinal association of vitamin B-6, folate, and vitamin B-12 with depressive symptoms among older adults over time.” The American journal of clinical nutrition 92.2 (2010): 330-335.
© 2010 American Society for Nutrition
Posted June 22, 2010.
References:
- Berg, Jeremy M., Lubert Stryer, and John L. Tymoczko. “Biosynthesis of Amino Acids.” Biochemistry. 6 ed. New York: W. H. Freeman, 2006. 691-693.
- Depression in Older Adults.” University of Michigan Health System. N.p., n.d.
- Melin, Gabrielle J., and M.D. “Depression and aging: Make sure to seek treatment – MayoClinic.com.” Mayo Clinic medical information and tools for healthy living – MayoClinic.com. N.p.,n.d.
- Skarupski, K.A.; et al; ” Longitudinal association of vitamin B-6, folate, and vitamin B-12 with depressive symptoms among older adults over time ”, in American Journal of Clinical Nutrition, published online June 2, 2010.
