Folate is a nutrient, part of the family of B vitamins, that has an important role in health.  It is a critical nutrient in pregnancy in order to prevent spina bifida, a birth defect.  In the brain, folate was thought to have several possible effects.  Its role in possibly lowering the risk of stroke in certain groups of people was recently reinforced by a study in a major medical journal.  In addition, it was thought that older adults with high levels of folate have a lower risk of developing dementia.

However, two recent research papers found that high folate levels might actually raise the risk of dementia in certain individuals – persons with low levels of Vitamin B-12.  Even more worrisome is the complex and now even more confusing relationship of folate to the risk of cancer.  New research suggests that folate might increase the speed of development of certain cancers.  While folate is important for the body in keeping its DNA genetic machinery working properly and therefore perhaps lowering the risk of cancer, it is also an important component of cell growth, hence perhaps enhancing the risk of cancer. 

The bottom line is far from clear at this time.  The most prudent path, until medical science further sorts this out, may well be to rely on the folate that is present naturally in foods and avoid extra supplementation of folate in the diet.