But you can get other benefits from coffee that
have nothing to do with caffeine. "Coffee is loaded with antioxidants, including
a group of compounds called quinines that when administered to lab rats,
increases their insulin sensitivity" he tells WebMD. This increased sensitivity
improves the body's response to insulin.
That may explain why in that new Harvard study,
those drinking decaf coffee but not tea beverages also showed a reduced diabetes
risk, though it was half as much as those drinking caffeinated coffee.
"We don't know exactly why coffee is beneficial
for diabetes," lead researcher Frank Hu, MD, tells WebMD. "It is possible that
both caffeine and other compounds play important roles. Coffee has large amounts
of antioxidants such as chlorogenic acid and tocopherols, and minerals such as
magnesium. All these components have been shown to improve insulin sensitivity
and glucose metabolism."
Meanwhile, Italian researchers credit another
compound called trigonelline, which gives coffee its aroma and bitter taste, for
having both antibacterial and anti-adhesive properties to help prevent dental
cavities from forming. There are other theories for other conditions.
Children and Coffee
How does this brew affect growing minds and
bodies? Very nicely, it seems, says DePaulis. Coffee, as you probably know,
makes you more alert, which can boost concentration. But claims that it improves
a child's academic performance can be exaggerated. Coffee-drinking kids may do
better on school tests because they're more awake, but most task-to-task lab
studies suggest that coffee doesn't really improve mental performance, says
But it helps kids' minds in another way. "There
recently was a study from Brazil finding that children who drink coffee with
milk each day are less likely to have depression than other children," he tells
WebMD. "In fact, no studies show that coffee in reasonable amounts is in any way
harmful to children."
On the flip side, it's clear that coffee isn't
for everyone. Its legendary jolt in excess doses -- that is,
more than whatever your individual body can tolerate -- can increase
nervousness, hand trembling, and cause rapid heartbeat. Coffee may also raise
cholesterol levels in some people and may contribute to artery clogging. But
most recent large studies show no significant adverse affects on most healthy
people, although pregnant women, heart patients, and those at risk for
osteoporosis may still be advised to limit or avoid coffee.
The bottom line:
"People who already drink a lot of coffee don't have to feel 'guilty' as long as
coffee does not affect their daily life," says Hu. "They may actually benefit
from coffee habits in the long run."
Originally published Jan. 26, 2004.
Medically updated March 4, 2005.
SOURCES: Tomas DePaulis, PhD,
research scientist, Vanderbilt University's Institute for Coffee Studies;
research assistant professor of psychiatry, Vanderbilt University Medical
Center, Nashville. Terry Graham, PhD, University of Guelph, Canada. Frank Hu,
MD, PhD, associate professor of nutrition and epidemiology, Harvard School of Public Health, Boston. Hu, F.
Annals of Internal Medicine, January 2004; vol 140; pp 1-8. Benedetti MD,
Neurology, July 12, 2000; vol 55; pp 1350-1358. Ross, G. The
Journal of the American Medical Association, May 24, 2000; vol 283; pp
2674-2679. Gazzani, G. Journal of Agricultural and Food Chemistry, Feb.
27, 2000. Leitzmann, M. The Journal of the American
Medical Association, June 9, 1999, vol 281; pp 2106-2122. Giovannucci, E.
American Journal of Epidemiology, June 1, 1998; vol 147; pp 1043-1052.
Pagano, R. Chest, August 1988; vol 94; pp 387-389.
© 2004 WebMD Inc. All rights reserved.