Thu Oct 31,10:24 AM ET

NEW YORK (Reuters Health) - Elderly women who drank relatively large amounts of coffee over their lifetimes appear to out-perform less frequent coffee drinkers in certain tests of mental abilities, according to new study findings.

Researchers from the University of California, San Diego in La Jolla found that women who reported being frequent lifetime coffee drinkers performed better than non-coffee drinkers in memory tests involving words and shapes, and in calculation and category tests, in which they named as many animals as they could in 1 minute.

Women at least 80 years old who were lifetime coffee drinkers outperformed their peers on 11 out of 12 tests, although the results did not reach statistical significance. This suggests that the relationship between coffee and mental acuity may become stronger as women age, the authors report.

These findings are supported by previous research that suggests that caffeine--of which coffee is the main source--produces certain effects in the body that improve memory and repair memory impairments.

People tend to experience a decline in their mental functioning from age 60 on, the researchers note, and the current findings suggest that, in women, coffee may counteract that process.

"It is biologically plausible that caffeine lessens age-related cognitive decline," Dr. Marilyn Johnson-Kozlow and her colleagues write in the recent issue of the American Journal of Epidemiology.

The investigators obtained their findings from tests of mental acuity in 890 women and 638 men. Participants were, on average, around 73 years old.

During the study, the participants completed questionnaires regarding how many cups of coffee they drink on an average day, and the number of years they had been coffee-drinkers. Regular coffee drinkers were considered to be those who drank at least one cup of coffee each month, and the highest category of consumers included people who currently downed approximately 5 cups each day.

Johnson-Kozlow's team found that women who drank relatively large amounts of coffee over their lifetimes outperformed their peers in tests where they had to recall a list of words and reproduce a geometric form after a delay of 30 minutes. High lifetime female coffee drinkers also did better on tests where they counted backward from 100 in multiples of seven, and spelled the word "world" backwards.

The link between coffee consumption and mental abilities persisted when the authors factored in the effects of certain potential confounders, such as age, education, and whether the women had received estrogen replacement therapy, which previous studies have suggested may boost memory.

However, coffee drinking was not linked to all of the tests designed to measure participants' mental acuity, the authors note, suggesting that caffeine may have a "differential effect," improving mental functioning in some areas, but not others.

In terms of why mental functioning wasn't linked to coffee drinking in men, the researchers suggest that the number of men included in the study may not have been large enough to detect an effect. Alternatively, they propose that some silent factor may be either clouding the relationship in men, or creating a false relationship in women.

However, men and women may also simply respond differently to caffeine, Johnson-Kuzlow and her colleagues add. "Gender differences may be due to pharmacodynamic differences in sensitivity to caffeine effects between men and women," they suggest.

SOURCE: American Journal of Epidemiology 2002;156:842-850.

-- Anonymous, October 31, 2002

Answers

'cuse me, my coffee's cold, gotta heat it up! hehehehe

-- Anonymous, November 01, 2002

I'm sure that blondes were rated on an adjusted scale. LOL

-- Anonymous, November 01, 2002

I drink at least a cup of coffee a day and I'm sure it, um, there's a big, um--what was the question?

-- Anonymous, November 01, 2002

By golly I knew gulping java 'til I shake my teeth loose was gonna make a difference in the end.

-- Anonymous, November 01, 2002