Does Beta-Carotene Preserve Memory?
Study Shows Supplements May Help Keep Thinking Skills Sharp
WebMD News Archive
Beta-Carotene and Memory continued...
The men were all in good health when they started the studies. Those who had
taken part in the original study were about age 73 when the sequel study began;
the new recruits were about 56 on average.
The men were followed up through 2003, completing yearly questionnaires
about their health and their compliance with taking the pills. Their cognitive
functioning was tested by telephone at least once between 1998 and 2002.
"The focus was on verbal memory," Grodstein tells WebMD. For
instance, researchers would read a list of words and ask the participants to
read them back immediately and again 20 minutes later.
"We found [in] the men who had been on beta-carotene long term -- 18
years [on average] -- their memory was significantly better than the placebo
group," Grodstein says. In the 18-month interval between studies, she says,
some of the men in the original study may have stopped the beta-carotene
Grodstein says she would categorize that improvement as modest. Even so, she
says, modest improvement may lead to substantial differences in a person's
eventual risk of getting dementia. Taking the supplements short term had no
effect, she says.
The study is published in the Nov. 12 issue of Archives of Internal
Medicine. The research was supported by grants from the National Institutes
of Health, BASF Corp. (which makes a beta-carotene supplement), and others.
The unusual study design, in which some participants were carried over from
the other study and kept their original assignments, may have affected the
results, says Peifeng Hu, MD, staff geriatrician at Santa Monica-UCLA Medical
Center & Orthopaedic Hospital, Calif. Hu is also assistant professor
of geriatric medicine at the University of California Los Angeles David Geffen
School of Medicine.
The findings don't warrant recommending supplements of beta-carotene, he
says. "I would not change my practice based on this study," says Hu,
who found in his own research that high blood levels of beta-carotene (not
necessarily from supplements) reduced the risk of cognitive decline in people
genetically predisposed to get Alzheimer's. His study findings were published
in 2006 in the Journal of Gerontology.