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

By Miranda Hitti
WebMD Medical News

Reviewed By Michael Smith, MD

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 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 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. 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.

Results showed that caffeine reduced the men's ability to process blood sugar. It also interfered with insulin, the body's hormone that handles blood sugar.

Since exercise has been shown to help blood sugar and insulin, the researchers wanted to see if exercise could offset caffeine's effects.

The men spent 13 weeks on an aerobic exercise program. The men walked or jogged on a treadmill for an hour, five times a week, at moderate intensity. Weight loss wasn't a goal, so they ate more to make up for burned calories.

Exercise didn't make up for caffeine's setbacks. Even when the men worked out, they still had blood sugar and insulin problems while taking caffeine.

Coffee May Not Be to Blame

But what about the studies that show that coffee may protect against type 2 diabetes?

A year ago, The Journal of the American Medical Association reported that people who drank at least 3-4 cups of coffee per day had a nearly 30% lower risk of developing type 2 diabetes.

Here's the catch. In the new study, caffeine came from a pill. But most people get their caffeine from drinks that have other ingredients.

"Coffee contains many other substances besides caffeine, such as potassium, antioxidants, and magnesium," write the researchers, who included Robert Ross, PhD, of Queen's University. Perhaps those other substances are helpful, but that's not certain.

The study appears in the March issue of Diabetes Care.

SOURCES: Lee, S. Diabetes Care, March 2005; vol 28: pp 566-572. WebMD Medical News: "More Americans Getting a Caffeine Buzz." WebMD Medical News: "Drinking Lots of Coffee May Prevent Diabetes."

http://my.webmd.com/content/article/101/106476.htm

very interesting, thank you for sharing. it would make sense to me that there would be a difference between a staight caffiene pill and something such as coffee that has other properties as well. who knew the difference could be the difference between harm and good though. definitely something to think about. before i started this woe, i found that my morning coffee was dropping my bs levels. i'm not sure of the why and how of it, but it was the coffee and perhaps the obscene amount of sugar i put in it it didn't spike before it dropped though, and the next thing i'd know, it would be in the 50's and i'd be a shaking mess. that's the part i never could figure out. it was my husband that clued me in on caffiene and bs dropping and yet i couldn't find too much information about it. since i have started this woe, i haven't had any such problem. i do still get the shakes and lightheadedness once in a blue moon, but my bs levels are not out of line at the time, usually between 69 and 83.

Very interesting. Thanx for sharing. I guess I am ahead of the game if I avoid coffee and caffeine containg sodas though. Those things make me go nuts and I can't concentrate though it makes the morning a little rougher...:-)

wish it wired me that way, it doesn't. i can drink two pots and go right to sleep. if i don't have it though, i can't keep my eyes open .

Chocolate has several health benefits, too! The People's Pharmacy did a show on it (NPR) recently.

Thanks, I'll keep on chuggin' my daily Joe!

I used to be addicted to caffiene. I couldn't keep my eyes opened until I had my sugar soda (before I was lc.) I realized I was addicted when on the weekends I wouldn't have soda so I would then get a headache. So I went cold turkey. I got a massive headache at first and felt a little like I did when I got the induction flu but eventually I got over it. Now, soon after I wake up I feel more awake than I used to after I had the soda. I needed the caffiene to wake up because I was an addict but after I quit I felt even more awake without the need for a chemical. Just a thought for those that still need their caffiene. Caffiene can hurt wieght loss and I just don't like being addicted to something.

Thanks so much I have several family member who could really use this article. Really appreciate you taking the time to post it.