Vitamin D does so much; it goes way beyond preventing rickets. We know it plays a role in cancer prevention, priming immune function, bettering heart disease and has even been suggested as a buffer against autism (when loaded with vitamin D, some children have made remarkable recoveries).

Now there may be a similar role in adult cognitive function.

Katherine Tucker, from Tufts University (Massachusetts, USA), and colleagues studied more than 1,000 men and women, ages 65 to 99 years, receiving home care, assessing vitamin D blood levels (measured as 25-hydroxyvitamin D, or 25(OH)D) and conducting neuropsychological tests.

Those with adequate vitamin D scored significantly higher on tests of cognitive performance, particularly on measures of “executive performance,” such as cognitive flexibility, perceptual complexity, and reasoning, as compared to those in the deficient and insufficient categories.

What was perhaps shocking was that only 35% of the patients had adequate healthy  vitamin D blood levels.

[Jennifer S. Buell, Tammy M. Scott, Bess Dawson-Hughes, Gerard E. Dallal, Irwin H. Rosenberg, Marshal F. Folstein, Katherine L. Tucker. “Vitamin D Is Associated With Cognitive Function in Elders Receiving Home Health Services.” J Gerontol A Biol Sci Med Sci, 2009 64A(8): 888-895; doi:10.1093/gerona/glp032.]

Be sure to supplement vitamin D (as D3) at a minimum of 2,000 IU daily. Up to 4,000 is quite safe and even then may barely bring a deficient person up to correct nutritional status of this remarkable and versatile vitamin.