Coffee, especially the decaffeinated kind, seems to offer protection against adult-onset diabetes, a study said Monday.
What causes the apparent effect is unclear, the report from the University of Minnesota said, but it is possible that minerals and non-nutritive plant chemicals found in rich amounts in the coffee bean may favorably affect blood-sugar levels or protect the pancreas from stress.
The finding, published in the Archives of Internal Medicine, was based on a study of more than 28,000 post-menopausal women in Iowa who were followed for 11 years.
When the study of the Iowa women began, more than 14,000 of them — about half — drank one to three cups of coffee per day, 2,875 drank more than six cups, 5,554 four to five cups, 3,231 less than one cup and 2,928 none.
Over the 11 years of the study 1,418 of the women reported on surveys that they had been newly diagnosed with type 2 diabetes.
Women who drank more than six cups of any type of coffee per day were 22 percent less likely than those who drank no coffee to be diagnosed with diabetes, the study found. Those who drank more than six cups of decaffeinated coffee daily had a 33 percent risk reduction compared with those who drank no coffee at all, it said.
While the implication is that something other than caffeine is at work, the study was not equipped to explore causes, the report said. Previous studies are mixed on whether caffeine increases or lessen diabetes risk among adults.
One earlier study in Finland, which has the highest coffee consumption in the world, found that men and women who drank 10 or more cups of coffee per day has the lowest risk of adult onset diabetes, the new report said, though in Finland decaffeinated coffee is not widely consumed.
“Although the first line of prevention for diabetes is exercise and diet, in light of the popularity of coffee consumption and high rates of type 2 diabetes mellitus in older adults, these findings may carry high public-health significance,” the study concluded.
