14/01/2011 11:18 GMT | Updated 22/05/2015 10:12 BST

Four Cups Of Coffee A Day Protect Against Diabetes

How many times have you read that drinking too much coffee is bad for you? Caffeine is a stimulant that can affect the heart and central nervous system, and in the short term it may increase your blood pressure. It has even been linked with an increase in cholesterol. But many scientists believe there's not really any evidence that coffee can harm you in the long term.

Coffee-and-coffee-beans Drinking coffee could ward off type 2 diabetes. Photo: Getty, Yuri Arcurs

And now there's more good news for coffee fans. According to researchers from the University of California, drinking four cups of coffee a day can slash a woman's risk of developing type 2 diabetes by more than half.

It's not the first time drinking coffee has been linked with a lower risk of type 2 diabetes, but the Californian researchers believe they've discovered why. What they found was that drinking coffee raises the level of a substance called sex hormone-binding globulin (SHBG) in your bloodstream. And higher levels of SHGB are already known to lower your risk of developing type 2 diabetes.

The study, published in the journal Diabetes, followed 359 women with diabetes and 359 who didn't have the disease over a period of ten years. The women who had four cups of coffee (caffeinated) a day were 56 less likely to develop type 2 diabetes than non-coffee drinkers.

Can you do without your daily caffeine jump-start?

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