Long-term beta carotene supplementation may help prevent cognitive decline

Nov 12, 2007

Men who take beta carotene supplements for 15 years or longer may have less cognitive decline, according to a report in the November 12 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Decreases in cognitive ability—thinking, learning and memory skills—strongly predict dementia, a growing public health issue, according to background information in the article. Long-term cellular damage from “oxidative stress” may be a major factor in cognitive decline. Some evidence suggests that antioxidant supplements may help preserve cognition, although previous studies have been inconclusive, the authors note.

Francine Grodstein, Sc.D., of Brigham and Women’s Hospital (BWH) and Harvard Medical School, Boston, and colleagues studied the antioxidant beta carotene and its effect on cognitive ability in two groups of men. The long-term group included 4,052 men who in 1982 had been randomly assigned to take placebo or 50 milligrams of beta carotene every other day. Between 1998 and 2001, an additional 1,904 men were randomly assigned to one of the two groups. Both groups were followed through 2003, completing yearly follow-up questionnaires with information about their health and their compliance with taking the pills. The men were assessed by telephone for cognitive function at least once between 1998 and 2002.

The long-term participants were treated for an average of 18 years and the short-term participants for an average of one year. Men in the short-term group displayed no differences in cognition regardless of whether they took beta carotene or placebo, but men in the long-term group who took beta carotene had significantly higher scores on several of the cognitive tests compared with men who took placebo.

“In this generally healthy population, the extent of protection conferred by long-term treatment appeared modest; nonetheless, studies have established that very modest differences in cognition, especially verbal memory, predict substantial differences in eventual risk of dementia; thus, the public health impact of long-term beta carotene use could be large,” the authors write.

Beta carotene is not without risks—for example, it may increase the risk of lung cancer in smokers, the authors note. However, its benefits against dementia surpassed those of other medications tested in healthy older people. “Thus, the public health value of beta carotene supplementation merits careful evaluation,” the authors conclude. “Moreover, as these data support the possibility of successful interventions at early stages of brain aging in well-functioning subjects, investigations of additional agents that might also provide such neuroprotection should be initiated.”

Source: JAMA and Archives Journals

Explore further: A novel therapy for sepsis?

add to favorites email to friend print save as pdf

Related Stories

Researchers measure ozone-depleting bromine

14 minutes ago

How much does bromine affect stratospheric ozone? Answering this question is the primary objective of measurements by a multi-instrument gondola carried by a high-altitude balloon. The gondola accommodates ...

Making videogames more fun for passive audiences

24 minutes ago

You might think watching other people play videogames is boring, but researchers at the Microsoft Centre for Social Natural User Interfaces (SocialNUI) at the University of Melbourne say it does not have ...

Recommended for you

A novel therapy for sepsis?

19 minutes ago

A University of Tokyo research group has discovered that pentatraxin 3 (PTX3), a protein that helps the innate immune system target invaders such as bacteria and viruses, can reduce mortality of mice suffering ...

Cellular protein may be key to longevity

Sep 15, 2014

Researchers have found that levels of a regulatory protein called ATF4, and the corresponding levels of the molecules whose expression it controls, are elevated in the livers of mice exposed to multiple interventions ...

Gut bacteria tire out T cells

Sep 15, 2014

Leaky intestines may cripple bacteria-fighting immune cells in patients with a rare hereditary disease, according to a study by researchers in Lausanne, Switzerland. The study, published in The Journal of Experimental Me ...

User comments : 0