About 225 more people in Ontario who are severely obese will have access to bariatric surgery, also known as "stomach stapling," the province's health minister announced on Friday.

"For some patients who have already been fighting severe weight problems through diet and exercise, bariatric surgery is a medical treatment of last resort," Health and Long-term Care Minister George Smitherman said.

The extra surgeries will take place in Toronto at the Humber River Regional Hospital, which is expanding its centre for bariatric surgery.

Bariatric surgery such as gastric bypass surgery involves shrinking the stomach to reduce a patient's diet after people have unsuccessfully tried to lose weight through diet, increased physical activity and anti-obesity drugs.

Research suggests the surgery is one of the most successful methods for long-term weight loss in obese people, who lose an average of 77 pounds. Shedding the extra weight helps lower incidence of Type 2 diabetes, high blood pressure and heart attacks.

The funding includes $3.7 million to boost the hospital's surgical capacity and  $124,300 in capital funding for renovations to the bariatric surgical suite.

In Canada, most provincial health plans pay for the surgery but demands outstrips supply.

There are about 20,000 morbidly obese patients in southern Ontario. About 4,500 people seek bariatric surgery each year, but fewer than 300 have the surgery in Canada.

Between 2002 and 2004, seven centres, including ones in Vancouver, London and Ottawa, stopped performing the procedure.