Caffeine intake makes insulin more resistant to changes in blood sugar levels, Canadian researchers report.

The researchers evaluated sugar metabolism in 23 men before and after a three-month exercise program. Before and during the exercise program, the men were given caffeine or a placebo. The subjects included 8 sedentary lean men, 7 obese men with type 2 diabetes, and 8 obese men without diabetes. Before the exercise program, caffeine reduced insulin sensitivity by 33% in the lean and obese men and 37% in the obese men with diabetes compared to placebo. After the exercise program, insulin sensitivity fell 23% after caffeine intake in the lean men, 26% in the obese men, and 36% in the obese diabetic men. Comparison of the two study phases showed that exercise did not improve insulin resistance related to caffeine intake. It seems that caffeine weakens or offsets any of the beneficial effects of exercise or weight loss on insulin resistance. While the clinical implications remain unclear, the findings are a "red flag" for doctors and are particularly important for obese patients and those with diabetes.

Don't go throwing-away your Starbucks gift card - although the effects of caffeine on insulin were duly noted, the fact remains that coffee may cut the risk of diabetes. Although the findings seem to contradict recent reports that coffee intake may cut the risk of diabetes, coffee contains several other substances that may affect sugar metabolism, such as antioxidants, potassium and magnesium. Caffeine without all of the other substances that are found in coffee produces a different result. Like peanut butter and chocolate - peanut butter by itself is a high-fat protein. When you combine it with chocolate you have a melodic mix disdainfully referred to as candy but happily celebrated in the form of a REESE'S Peanut Butter Cups. It's all in the delivery, folks.