Decaf may prevent diabetes

ORLANDO, Fla. – Here’s something to go with your morning cup of joe: A new 11-year study has found yet another potential benefit of coffee.

Researchers said Monday that women who drank six or more cups of decaffeinated coffee a day were 33 percent less likely to develop type 2 diabetes, a disease that affects more than 18 million Americans.

But while the findings sound encouraging for avid coffee drinkers, the American Diabetes Association is warning against reading too much into the data.

“I think it’s intriguing and it suggests if you enjoy coffee – particularly decaffeinated coffee – then it’s reasonable to drink it,” said Dr. Robert Rizza, president of the American Diabetes Association and a professor at the Mayo Clinic College of Medicine in Minnesota. “But I would do so in moderation.”

The study, which followed other research this month showing that coffee may help prevent cirrhosis, was published Monday in the Archives of Internal Medicine.

It looked at diabetes risk among nearly 29,000 postmenopausal women in Iowa who were followed from 1986 to 1997. The women were being tracked for a larger project on cancer.

Epidemiologist Mark Pereira and his colleagues used questionnaires on the women’s eating and drinking habits to look for an association between coffee consumption and diabetes. At first glance, Pereira said the data indicated that drinking six or more cups of any coffee – decaf or regular – was linked to a 22 percent reduction in diabetes risk.

But when researchers teased out the caffeinated-versus-decaffeinated drinkers, they found that the benefit was strong only among the women who drank six or more cups of decaf. And in that case, the risk reduction was even higher, at 33 percent.

Pereira, an associate professor at the University of Minnesota, said coffee might play a role in how the body regulates sugar.

In type 2 diabetes, patients no longer break down sugar properly. The imbalance causes damage to various organs, and diabetics run the risk of serious complications such as kidney failure, blindness and circulation problems.

Pereira said coffee is rich in antioxidants, which may protect the cells in the pancreas that produce insulin – the hormone that regulates sugar. In type 2 diabetes, patients either don’t make enough insulin to keep sugar levels under control or their insulin is ineffective.

Antioxidants are found in fruits, vegetables and other foods, but Pereira said most Americans are not eating the recommended servings of these every day. If the reduction in diabetes risk holds in more testing, he said, it’s possible that coffee could play a role in curbing the diabetes epidemic that already is under way in America.

“There’s quite a lot of people in our population who drink high amounts of coffee, and that’s not true with other sources of antioxidants like fruits and grains and vegetables,” Pereira said. “But it would be premature to make any public-health recommendations” based on current research alone.