One small change you can make today to improve insulin sensitivity

In the February 13th e-Alert, I wrote about how common-sense lifestyle changes can effectively prevent and treat Type II diabetes. A study of over 3,000 people found that a low-calorie, low-fat diet and regular exercise slashed patient’s Type II diabetes risk by more than half.

Those were some impressive results. But a new study suggests that they might have seen even BETTER results if they had made one more lifestyle change. This one doesn’t necessarily relate to fat, calories, or activity levels – yet it may make a big difference in your body’s ability to use insulin effectively.
World’s most widely consumed “drug” may be hidden key to insulin resistance

I’m talking about caffeine, one of the most widely consumed “drugs” in the world. In the Western world, the average daily intake per capita is about 300 mg – a little more than two cups of brewed coffee a day. Of course, it’s also found in tea, sodas, chocolate, and hundreds of other foods in varying amounts. And according to new research, it may be contributing to the insulin resistance epidemic sweeping the world.

A group of Dutch doctors recruited 21 healthy, lean, non-diabetic men and women under the age of 30 to compare the effects of caffeine, a drug called dipyridamole, and placebo on insulin sensitivity. (Insulin sensitivity is the medical term to describe how efficiently the body secretes and uses insulin to bind glucose and transport it through cell membranes; increasing insulin sensitivity is positive, while decreasing insulin sensitivity is negative.) Dipyridamole, an anticoagulant drug also known by the brand name Persantine, was chosen as a point of comparison because its effects on hormone action are directly opposite to those of caffeine.

The participants were divided up into two groups: the first group to compare caffeine with placebo (11 people) and the second to compare dipyridamole with placebo (nine people). (One person participated in both arms of the study.) Each participant in each group was tested twice, with at least three weeks in between sessions. Before a test, each participant fasted overnight and abstained from all sources of caffeine for three days. Periodic blood samples were collected and baseline values were established. Thirty minutes after the baseline values were assessed, participants received glucose, insulin, and the test substance (caffeine, dipyridamole, or placebo). The test substances were first given in a loading dose, followed by a continuous infusion for two hours. Blood levels were monitored every five minutes during that time.
Caffeine may cancel out effects of prescription drugs

The researchers found that dipyridamole had no effect on insulin sensitivity – while caffeine decreased insulin sensitivity by about 15 percent. That might not seem like a lot, but the authors made an interesting observation: it’s about the same effect that prescription diabetes drugs like metformin (Glucophage) have, only in reverse. In other words, Glucophage increases insulin sensitivity about 15 percent – so if you take a drug for Type II diabetes and wash it down with a few cups of coffee, you may be canceling out its effects.

That’s another important point to consider: it didn’t take an entire pot of coffee to cause a problem with insulin sensitivity. While the study didn’t state a practical equivalent in terms of cups of coffee or cans of soda, it did say that the researchers “aimed at a stable caffeine concentration of 5 – 10 mg per liter.” And according to the study, that concentration is “a dose that equals moderate consumption.”

We all may have different definitions of “moderate consumption.” But if you struggle with insulin resistance or full-blown Type II diabetes, your best bet might be zero caffeine consumption. I know this can be a challenge for those of us addicted to our morning coffee, but you can usually beat a caffeine habit within a week. This study suggests that giving up caffeine might be another important change you can make to protect yourself from one of today’s most prevalent diseases.

Source: Diabetes Care 25:364-369, 2002

Copyright 1997-2002 by Institute of Health Sciences, L.L.C.