Beta carotene protects memory in study

Beta carotene protects memory in study
A split-view image showing PET scans of a normal brain (L) and a brain with Alzheimer's disease. Beta carotene taken as a dietary supplement for many years may protect against declines in memory, thinking and learning skills that often precede Alzheimer's disease, researchers said on Monday. (National Institute on Aging/Handout/Reuters)WASHINGTON (Reuters) - Beta carotene taken as a dietarysupplement for many years may protect against declines inmemory, thinking and learning skills that often precedeAlzheimer's disease, researchers said on Monday.
The study, published in the Archives of Internal Medicine,pointed to a protective effect against cognitive decline inhealthy men who look beta carotene for about 18 years, but notin men who took the supplements for an average of a year.
The findings indicate beta carotene may be an importantweapon in warding off memory problems that may foreshadowAlzheimer's and other forms of dementia, the researchers said.
"This is the first trial that has found any way to helpyour memory if you're healthy. I think it does tell us that wecan change how our memory improves or worsens," FrancineGrodstein of Brigham and Women's Hospital in Boston, who ledthe study, said in a telephone interview.
Taking beta carotene may have risks for some people such asraising lung cancer risk in smokers, Grodstein said.
Beta carotene is one of the antioxidants -- substances thatprevent some of the damage from unstable molecules known asfree radicals -- created when the body turns food into energy.Some experts think antioxidants can lower the risk of cancer,heart disease and other ailments.
"Beta carotene is an antioxidant vitamin. So the reason wethought it might help your brain is because there is now a lotof evidence that oxidative damage harms your brain. And thatmay be one of the initiating factors which leads to memoryproblems," Grodstein said.
In this study, researchers examined the effects of betacarotene on cognitive ability in two groups of men.
Those in a group of 4,052 men were randomly assigned in1982 to take either 50 milligrams of beta carotene or a placeboevery other day. Another 1,904 men between 1998 and 2001 werealso randomly assigned to take either the same amount of betacarotene or a placebo every other day.
The men in the long-term group took the supplements for anaverage of 18 years. The men in the short-term group did so foran average of a year, with the longest being three years.
Men who took beta carotene in the long-term group recordedsignificantly higher scores on several cognitive tests --particularly tests of verbal memory -- compared with those whotook a placebo, the study found. In the short-term group, themen taking beta carotene did no better in cognitive tests.
In an editorial accompanying the study, Dr. Kristine Yaffeof the San Francisco Veterans Affairs Medical Center andUniversity of California at San Francisco sounded a note ofcaution, saying studies have yielded mixed results aboutantioxidant supplements and better cognitive outcomes.
"For the clinician, there is no convincing justification torecommend the use of antioxidant dietary supplements tomaintain cognitive performance in cognitively normal adults orin those with mild cognitive impairment," Yaffe wrote.
Another study also examined the link between diet anddementia. French researchers, writing in the journal Neurology,tracked the diets of 8,085 men and women over age 65. They werefollowed for four years, during which 183 of the participantsdeveloped Alzheimer's and 98 developed some other dementia.
Risk for developing dementia was found to be lower in thosewith diets heavy in fish, omega-3 oils, fruits and vegetables.
(Editing by Julie Steenhuysen and Todd Eastham)