Sorry, you'll still have to exercise

Good press for diet pills: lifestyle change combined
with orlistat can help prevent Type II diabetes

By Brian Hoyle

We are what we eat, the old saying goes. For many people in Canada who take their visits to the buffet table a bit over-zealously, a calorie- and cholesterol-filled diet combined with an inactive lifestyle can spell disaster when it comes to their health. It's well known that being overweight puts a person at risk for developing Type II diabetes. This comes as bad news to the millions of Canadians who are overweight or clinically obese, since upwards of 90% of them will become diabetic over the coming decade. This will swell the rolls of diabetic Canadians by nearly two million.

Aside from the personal worry and health risk that Type II diabetes creates, the added burden will strain our already creaky healthcare system. So anything that can lessen the risk of developing diabetes is welcome. A paper published in the January issue of Diabetes Care may give more hope to those battling a bulging waistline.

The paper chronicles the results of the XENical in the Prevention of Diabetes in Obese Subjects (XENDOS) study. XENical is the trade name of the drug orlistat that is marketed by Hoffman-La Roche. The drug blocks a particular enzyme that digests fat, and so acts to lessen the amount of fat absorbed by the body. The end result is weight loss.

The approach of the XENDOS study was that adding a weight-reducing agent to lifestyle changes, principally increased exercise and a calorie- and cholesterol-reduced diet would take weight off and keep it off better than just the lifestyle changes alone. This would, the authors proposed, lead to fewer people developing Type II diabetes.

The double-blind study was devised by scientists at Sahlgrenska University Hospital in Göteborg, Sweden, and Hoffman-La Roche. The participants -- 3,304 between 1997 and 2002 -- were obese, glucose tolerant or intolerant non-diabetics. Each participant's blood glucose levels were measured every six months and body weight was measured every three months for four years. The design of the study and the huge number of people involved makes the data very powerful and very likely an accurate picture of what would result in the "real world."

Both the study and control groups showed a large weight loss in the first year, followed by a gradual weight gain over the next three years. While neither group gained back all the lost weight, almost a quarter of all those taking orlistat were still over 10% lighter after four years, versus only a tenth of those who did not receive the drug. Most study participants reaped the benefits of their healthier lifestyle, including lower blood pressure, improved levels of cholesterol, and a trimmer waistline. These improvements were even more pronounced in the orlistat group.

Charting who developed diabetes and who did not revealed even more dramatic results. The study group had a 37% decreased risk of developing Type II diabetes than the control group. For those who were glucose intolerant, orlistat reduced the progression to Type II diabetes by a whopping 52%, compared to lifestyle changes alone. These benefits of orlistat did not come at the expense of side effects. Both the study and control groups experienced difficulties (mainly intestinal upset) at the same rate.

This latest research is good news to those in the diabetes trenches in Canada. "Given the fact that we are in the midst of an epidemic, with the number of Canadians with diabetes expected to double over the next 15 years, any strategy that will help to reduce the risk of developing this disease is certainly most welcome," says Dr Lawrence Leiter, Head of Endocrinology and Metabolism, St Michael's Hospital in Toronto.