Effect of vitamin and trace-element supplementation on cognitive function in elderly subjects

To determine whether supplementation with vitamins and trace elements in modest amounts influences cognitive function in apparently healthy, elderly subjects.

The study was designed as a randomized, double-blind, placebo-controlled trial. Ninety-six, apparently healthy, independent men and women older than 65 y of age were recruited and randomized to receive a supplement of trace elements and vitamins or a placebo daily for 12 mo. Blood-nutrient levels were estimated at baseline and at the end of the study. The major outcome measure assessed was cognitive function consisting of immediate and long-term memory, abstract thinking, problem-solving ability, and attention.

Eighty-six subjects completed the 1-y trial. The supplemented group showed a significant improvement in all cognitive tests (P < 0.001 to 0.05) except long-term memory recall (P > 0.1). Those whose blood-nutrient levels were below the reference standard showed lower responses on cognitive tests. There was no significant correlation between individual nutrient levels and performance on various cognitive function tests.

Cognitive functions improved after oral supplementation with modest amounts of vitamins and trace elements. This has considerable clinical and public health significance. We recommend that such a supplement be provided to all elderly subjects because it should significantly improve cognition and thus quality of life and the ability to perform activities of daily living. Such a nutritional approach may delay the onset of Alzheimer's disease.