As time goes by

As time goes by

As the old song goes: You must remember this folic acid helps keep your cognitive faculties sharp.

Okay, that’s not quite the way the old song goes (something about kisses and sighs), but it’s a very good thing to remember just the same.

It’s still the same old story

As we’ve seen in previous studies, high levels of the amino acid homocysteine may contribute to cognitive function problems ranging from mild memory loss to Alzheimer’s disease. Likewise, high levels of folate and other B vitamins (most notably B-6 and B-12) have been shown to lower homocysteine as well as the risk of cognitive decline.

But the question lingers: What about supplements of folic acid (synthetic folate)? Can folic acid also play a key role in curbing homocysteine and keeping the brain bright and sharp?

Two new studies shed considerable light.

Study number one appeared in an issue of The Lancet published last month. Researchers at the University of Wageningen in the Netherlands conducted a three-year, folic acid intervention.


  • Researchers recruited more than 800 men and women over the age of 50 with elevated homocysteine levels
  • Subjects were randomly assigned a daily supplement of 800 micrograms (MCG) of folic acid or a placebo
  • Periodic tests evaluated memory, information processing speed, and sensorimotor speed
  • Subjects who took folic acid increased blood levels of folate by more than 575 percent, and lowered homocysteine by more than 25 percent, compared to the placebo group
  • Memory, information processing speed, and sensorimotor speed were all significantly improved in the folic acid group, compared to the placebo group

In their conclusions, study authors summed it up succinctly: “Folic acid supplementation for 3 years significantly improved domains of cognitive function that tend to decline with age.”

The fundamental things apply

The second study comes from a January 2007 issue of the Archives of Neurology.


  • For more than six years, Columbia University researchers followed the dietary habits of 965 subjects over the age of 65 to assess Alzheimer’s disease (AD) risk in relation to folate, B-6, and B-12 intake
  • None of the subjects showed signs of dementia at the outset of the study
  • Neither folate alone nor folic acid alone produced a lower AD risk, but subjects who had the highest intake of folate and folic acid supplements COMBINED had a lower risk of AD, compared to subjects with the lowest folate and folic acid intake

The Columbia team also determined that intake of B-6 and B-12 was not related to AD risk. And while that may be true within the design of this study, previous research has shown that a combination of B-6, B-12, and folate are needed to metabolize homocysteine.

The best dietary sources of folate include spinach and other dark green vegetables, citrus fruits, broccoli, wheat germ, brewers yeast, lima beans, cantaloupe, watermelon, brown rice, peas, sprouts, poultry, shellfish, pork, and liver from organically raised animals.

You can find specific recommendations about folic acid supplementation from Jonathan V. Wright, M.D., and HSI Panelist Allan Spreen, M.D., in the e-Alert “Remember the Way to Memory Lane” (1/23/06):