Article #2:

A pleasing blend
By mixing exercise with caffeine, you decrease your risk of insulin
resistance
by Sarah Haines

morning coffee may jump start your day, but it may also increase your
susceptibility to diabetes, say U of G and Queen's University researchers.

Felicia Greer, a PhD candidate in Guelph's Department of Human Biology and
Nutritional Sciences; Bob Ross, an associate professor in the Faculty of
Health Sciences at Queen's University; and Bob Hudson, an endocrinologist at
Queen's, have found that a high intake of caffeine can increase insulin
resistance.

This phenomenon is related to a low uptake of glucose in the cells. Insulin
is a hormone that helps cells take up glucose in the blood. People who are
insulin-resistant are more susceptible to diabetes, high blood pressure and
cardiovascular disease.

"The impact of insulin resistance will be more serious for some people than
others," says Greer. "It will depend on their age, lifestyle and level of
fitness."

The insulin-resistant study involved eight healthy but sedentary males
between the ages of 24 and 30. During the trials, the participants received
either a placebo or a pure caffeine pill (the equivalent of two or three
cups of strong coffee) after withdrawing from caffeine consumption for 48
hours. Their insulin resistance was measured after each pill was consumed.

The researchers found that after participants ingested caffeine, their
ability to take up glucose was reduced by 20 to 25 per cent, which
translates into increased insulin resistance. In contrast, the placebo had
no effect on glucose take-up.

How serious are these findings? Depending on the health of the individual,
this added resistance could push those already at risk of acquiring diabetes
over the edge, says Prof. Terry Graham, Greer's adviser.

"An aging, sedentary population prone to obesity is creating cause for
concern," says Graham. "These tendencies, coupled with high rates of coffee
consumption can accumulate to have a very negative health impact for this
group."

The researchers don't know, however, whether coffee has the same effects on
insulin resistance that pure caffeine does. Intuitively, it seems that it
would, says Graham, but under other circumstances, they've found that coffee
and caffeine affect the body differently.

The good news is that regular exercise can reduce the insulin resistance
associated with caffeine consumption. Cutting out coffee altogether is not
necessary. Instead, moderate caffeine consumption balanced with a healthy
lifestyle is key, says Greer.

This research is supported by Natural Sciences and Engineering Research
Council, Gatorade and the Medical Research Council.