Biologist Studies Link Between Caffeine, Diabetes
Research could lead to important
potential treatment for diabetics
Terry Graham is exploring the relationship between caffeine,
found in drinks such as coffee and these boosting beverages,
and type-2 diabetes.
PHOTO BY MARTIN SCHWALBE
Canadians resolving to cut their caffeine intake
may reduce certain health risks as well, especially if obesity
and lack of exercise play a role in diets that are high
Prof. Terry Graham, Human Biology and Nutritional Sciences,
is part of a three-year tri-university effort researching
the link between caffeine use and type-2 diabetes, the most
common form of diabetes in Canada.
"The statistics in Canada and the western world are
startling," says Graham. "Cases are becoming increasingly
common and in younger age groups."
Type-2 diabetes is now common among people in their 40s,
and increasing obesity in children suggests it will continue
to affect younger age groups, he says.
Type-2 diabetes accounts for 90 per cent of diabetes in
Canada. Those with the disease can still produce insulin
- the body's blood glucose regulator - but Graham says they
can't produce enough to "get the job done" and
often have to take drugs to help manage blood sugar levels.
He says the two biggest risk factors are inactivity and
"We're finding caffeine can have an unhealthy effect
on insulin levels for people already at risk."
Graham's concern is based on his previous studies involving
caffeine's impact on exercise metabolism using two groups
of university-aged men - one group called "lean"
and the other "obese." The subjects were tested
using an oral glucose tolerance test, conducted with and
without prior caffeine ingestion. This work was performed
by graduate students Sara Chown, Heather Petrie and Laura
"Ideally, you want to produce the least amount of
insulin to get your body's glucose level down to normal,"
says Graham. "We found that obese individuals have
a resistance to insulin, which means they require higher
levels of insulin to adjust their glucose levels. When given
caffeine, their insulin levels go through the roof."
This research focused on short-term effects of caffeine,
but the new project will study some long-term effects surrounding
caffeine and type-2 diabetes. It will involve obese and
lean individuals between the ages of 40 and 60, with and
Among other long-term effects, the researchers will be
looking for signs that the body adapts in habitual caffeine
"Caffeine is often thought of as a benign drug,"
says Graham, "and in many ways, it is. But from what
we've seen so far, this research could lead to important
potential treatment for diabetics."
Graham's research, in addition to involving a number of
graduate students, involves research teams at two other
Canadian universities (headed by Bob Ross and Bob Hudson
at Queen's University and Arend Bonen at the University
of Waterloo) and Mary Van Soeren, formerly of Guelph General
This research is sponsored by the Natural Sciences and Engineering