Move over red wine, green tea and blueberry juice-black coffee may be the healthiest beverage of all... particularly if you want to prevent diabetes.

Standout scientific evidence: An international team of researchers from Australia, France, Holland, Scotland and the US analyzed data from 18 studies involving more than 500,000 people-and found a strong link between coffee consumption and the risk of diabetes. Compared with people who didn't drink any coffee...

• Each daily cup of coffee consumed (caffeinated or decaffeinated) was linked to a 5% to 10% reduced risk.

•Drinking 3 to 4 cups daily, to a 25% reduced risk.

• Drinking 6 cups daily, to a 40% reduced risk.

"It could be envisioned that we will advise our patients most at risk for diabetes to increase their consumption of coffee in addition to increasing their levels of physical activity and weight loss," wrote the researchers in the Archives of Internal Medicine.

How safe? "There are sometimes claims that coffee may do harm by increasing the risk for cardiovascular disease, but there is no evidence for this," says Lars Ryden, MD, a cardiologist and diabetes specialist at the Karolinska Institute in Sweden. "People may drink coffee safely."

Why it works: There are many ways that the compounds in coffee might protect against diabetes, says Rob M. Van Dam, PhD, assistant professor in the Department of Nutrition at the Harvard School of Public Health...

Magnesium works with enzymes that are a must for glucose metabolism and insulin sensitivity.

• Lignans (a plant compound) are anti-inflammatory antioxidants.

• Chlorogenic acids (antioxidants) reduce chronic inflammation (linked to the development of diabetes)... help produce enzymes that cut glucose output by the liver... reduce the intestinal absorption of glucose and improve insulin sensitivity.

Recent finding: In a three-month study, 47 habitual coffee drinkers stopped drinking coffee for one month, consumed four cups a day for the second month, and eight cups a day for the third month.

Higher coffee intake increased blood levels of chlorogenic acid and decreased two biomarkers of chronic inflammation. "Coffee consumption appears to have beneficial effects on subclinical inflammation," concluded researchers from the German Diabetes Center in the American journal of Clinical Nutrition.

Is Timing Everything?

In another recent study on coffee and diabetes, Brazilian researchers analyzed 11 years of health data from nearly 70,000 women.

Results: Those who drank more than one cup of coffee a day had a 34% lower risk of developing diabetes compared with those who didn't drink any.

Surprising finding: But the link between coffee consumption and diabetes was true only in women who drank coffee at lunchtime!

"Our findings strongly suggest that only coffee taken with lunch may reduce diabetes risk," wrote the researchers in the American journal of Clinical Nutrition.

A Good-For-You Cup Of Coffee

Research links every kind of coffee to a reduced risk of diabetes-caffeinated or decaffeinated, filtered or instant, taken black or with cream and sugar. But it's healthier for a person who wants to prevent or control diabetes to avoid regular intake of the high-calorie, high-sugar, high-fat coffee concoctions so commonly served at today's coffee shops, says Lori Barr, MD, a physician and self-described "vibrant living expert" in Austin, Texas.

Maybe you don't like unsweetened coffee . What should you do if you want to enjoy its protective effect?

Unsweetened coffee may be more flavorful than you imagine-if you drink the right kind of coffee, says Kenneth Davids, editor and principal writer of the web publication and author of Coffee: A Guide to Buying, Brewing, and Enjoying.

"The reason more people don't drink more black coffee is because they're not drinking good coffee," says Davids. "If you buy a good coffee, it has a natural balance of bitterness and sweetness that doesn't require sugar."

When Davids says good coffee, he means...

Fully ripened beans. "The coffee bean is a fruit," he says. "If the bean is picked when it's ripe, sweet and juicy, and the green and overripe beans are separated out, the coffee will have natural sweetness to it, regardless of the variety or where it's grown."

Medium roast. "Many people are into dark roasts, and dark roasts are typically served in coffee shops such as Starbucks," he says. "But a dark roast is bitter."

Bottom line: "I always encourage people to try a coffee with ripe beans, at medium roast, and discover whether they really need sugar-because a lot of people have never tasted coffee like that."

Finding Good Coffee

Davids provided this list of coffee companies that sell coffees that meet his criteria of ripeness and medium roast.

Large nationa-1 roasters: Green Mountain Coffee Roasters (www.keuriggreenmountain. com; 866-901-2739)

Medium-sized roasters with some national presence: Intelligentsia Coffee Roasters, Chicago (; 888-945-9786); Stumptown Coffee Roasters, Portland (, 855-711- 3385).

Small, elite roasters with the 'best possible coffees and good wholesale coffees on the Internet: Terroir Coffee, New England (www., 866-444-5282); Café Grumpy, New York City (, 212- 255-5511, 718-499-4404, 718-349-7623); PT's Coffee, Topeka, Kansas (, 888-678-5282); Klatch Coffee, southern California (, 877-455-2824); Barefoot Coffee, northern California (www., 408-293-7200); Paradise Roasters, Minnesota (www.paradiseroasters. com, 763-433-0626); Temple Coffee, Sacramento (, 916-454-1282).

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