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Caffeine Tied to Blood Sugar Problems

But Don't Be Too Quick to Blame Coffee, Say Researchers
WebMD Health News

Mar. 9, 2005 -- Caffeine can interfere with blood sugar.

But don't shelve your coffee mug just yet. Coffee might not be the culprit. In fact, it may offer some protection against diabetesit may offer some protection against diabetes, say researchers.

Sound confusing? The final verdict isn't in yet. Keep things simple by watching your caffeine intake from all sources. Besides coffee, caffeine is also found in some soft drinks, teas, and chocolate (in smaller amounts).

Caffeine's Buzz Is Common

Just about everyone has at least some caffeine every dayeveryone has at least some caffeine every day, and the numbers are rising for people aged 2-54 years.

Nearly 90% of U.S. adults and 76% of children have caffeine on a daily basis. Soft drinks are the top source for kids; for adults, coffee is No. 1, followed by soft drinks and teas. That's according to a study in January's Journal of the American Dietetic Association.

Checking nutritional labels doesn't always help. Food and drink makers don't have to list the amount of caffeine on the Nutrition Facts label.

Want to start tracking your caffeine? Here's how much caffeine is in popular drinks:

  • Coffee (8 ounces, brewed): about 135 mg
  • Caffeinated tea (8 ounces): about 50 mg
  • Coca-Cola (12 ounces): about 34.5 mg
  • Diet Coke (12 ounces): 46.5 mg

Charting Caffeine's Effects

Participants included 23 white men. Eight were lean, seven were obese and had type 2 diabetes, and eight were obese but did not have diabetes.

They drank up to 5 cups a day of coffee or tea, with two men favoring decaffeinated versions.

The men were then put through a test to determine the men's insulin sensitivity.insulin sensitivity. This is a measure of how well the body is responding to insulin, the hormone that controls blood sugar. If insulin sensitivity is decreased, blood sugar levels can rise. This is a sign that someone either has or is at increased risk of having diabetes.

Prior to the test the men were given either caffeine tablets equal to 2 to 3 cups of coffee or a placebo.

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