Suggestions that folate may play a role in mood and cognitive disorders is not far behind. What are the benefits of folate status and neurocognitive functioning.
Folic acid was identified three years prior to the identification of the role of vitamin B12 showing improvements to anemia in the resulting treatment. It has now been confirmed that folic acid appears to promote neurological problems in vitamin B12 deficient patients.However, because folate treatment does not affect the neurological lesions of the vitamin B12 deficiency, pernicious anemia, concern has been raised that random use of large folate supplements may mask and potentially aggravate the neurological consequences of a vitamin B12 deficiency in their early and more easily treated stages.
Vitamin B12 and folate are closely linked in the methylation process. It is therefore evident that a vitamin B12 deficiency can lead to a secondary folate deficiency in the retention of folate. It is proposed that low levels of vitamin B12 are linked with peripheral neuropathy and subacute combined degeneration of the spinal cord.
Folate on the other hand plays a more important role in cognition and mood, perhaps through effects on serotonin, dopamine and noradrenergenic systems. Recent research shows an association with folate and mild cognitive impairment (MCI) and some forms of dementia. However, a causative role is not yet clear-cut.
Considerable research supports the hypothesis that nutritional factors moderate cognitive brain functioning. Previous studies show an association between B vitamins and folate status and neurocognitive functioning in older people. It has been found that supplementation with B vitamins, including folic acid can decrease homocystein levels and produce changes in cognitive performance. Byron and colleagues found that when conducting cognitive and mood tests before and after supplementation of 750 mg folate to women for 35 days, a significantly improved performance in a speed-of processing tasks were observed in women who had initially lower folate levels. The effects of folate across different age groups were however, not consistent.
It seems that we have only begun to unravel the nature of the relationship between folate and mood and cognitive disorders. The role of folate in these disorders is not yet clear-cut, but there remains a compelling commonality to many of the research studies. It appears that folate may be predictive of treatment outcome in depression, perhaps through its role in homocystein or neurotransmitter metabolism. Suggestions that folate may play a role in the disease pathology of Alzheimer’s is not far behind either.
Clearly there is quite a complex relationship between nutrition and brain functioning and future research aims at determining optimal levels of folate-both in a healthy and in a disease state-as well as an understanding of folate and brain functioning by determining folate’s actions and the critical time points for these actions.
Safe upper limits of folic acid supplementation can be beneficial and appears to reduce the risk for vascular disease and some forms of cancer and plays a role in the improvements in mood and in some forms of cognitive decline.
Resources:
1. Olsen BH, Keast DR, Song WO, Morris DH. Effectiveness and Safety of Folic Acid Fortification. Olson:Nutrition Today. 2004;39:169-175.
2. D’Anci KE, Rosenberg IH. Folate and Brain Function. Curr Opin ClinNutr MetabolCare. 2004;7:659-664.
3. Moretti R, Torre P, Antonello RM, Cozzato G, Cattaruzza T, Scapicchio PL. Vitamin B12 and Folate Depletion. Neurology. 2004;10:338-343.
