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Caffeine May Hamper Blood Sugar Control

Caffeine at Mealtime May Cause Problems for People With Type 2 Diabetes

WebMD Health News

July 26, 2004 -- Caffeine may cause problems with blood sugar control after meals for people with type 2 diabetes, according to a new study.

Although more research is needed to confirm these results, researchers say their findings show that people with diabetes who have problems with glucose and insulin control should consider cutting back on caffeine in their diets.

The study showed that after a large dose of caffeine, blood glucose and insulin levels surge in response after meals in people with type 2 diabetes. These patients can have high insulin levels because they inefficiently use the hormone to lower blood glucose.

"In a healthy person, glucose is metabolized within an hour or so after eating. Diabetics, however, do not metabolize glucose as efficiently," says researcher James D. Lane, PhD, associate research professor in the department of psychiatry and behavioral sciences at Duke University, in a news release. "It appears that diabetics who consume caffeine are likely having a harder time regulating their insulin and glucose levels than those who don't take caffeine."

"The goal of clinical treatment for diabetes is to keep the person's blood glucose down," says Lane.

Caffeine May Interfere With Glucose Control

In the study, published in the August issue of Diabetes Care, researchers looked at the effects of caffeine on glucose and insulin levels in 14 people with type 2 diabetes who regularly drank coffee. None of the participants required insulin therapy as part of their diabetes treatment.

The participants were observed on two different mornings after an overnight fast and abstinence from caffeine.

On the observation days, the participants took their prescribed diabetes medications and provided a blood sample 30 minutes later. While still fasting they were then given two 125-milligram capsules of caffeine or a placebo. A cup of coffee contains from 80 milligrams to 175 milligrams of caffeine. A second set of blood tests were then analyzed an hour after the taking the pills.

Participants were then fed a liquid meal containing 75 grams of carbohydrates and another 125-milligram caffeine capsule or placebo. Additional blood samples were taken an hour and two hours following the meal.

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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