Use of weight-loss surgery has increased 10-fold in hospitals in England since 2000 and those who have gastric bands fitted can reduce their risk of early death and cut health service costs, scientists said on Friday.

In a study published in the British Medical Journal, researchers said one reason for the rapid rise in weight-loss procedures, or bariatric surgery, was increased demand from obese patients as they become more aware of surgery as a viable treatment option.

Bariatric surgery is performed on people who are dangerously obese, as a way of trying to help them lose weight.

The idea is to reduce the size of the stomach, either with a gastric band or a gastric bypass that re-routes the small intestines to a small stomach pouch, or by removing a portion of the stomach.

A team of researchers based at Imperial College London analysed data on weight-loss surgery for the NHS in England between April 2000 and March 2008 and found that a total of 6,953 bariatric procedures were carried during that time.

The number of operations rose more than 10-fold from 238 in 2000 to 2,543 in 2007, they said in a report of their findings.

Analysing outcomes for patients at 30 months and one year after surgery, the researchers found that those who had gastric banding had lower post-surgery death rates and had to be readmitted to hospital less and for shorter times than patients who had gastric bypass operations.

The National Institute for Health and Clinical Excellence (NICE), which assesses the cost effectiveness of medical treatments for the NHS, recommends bariatric surgery for people with morbid obesity.

This includes people with a body mass index (BMI) of at least 40, and those who have a BMI of at least 35 and are also suffering from other diseases that could be improved by weight loss.

BMI is equal to weight in kilograms divided by height in metres squared.

(Reporting by Kate Kelland; Editing by Steve Addison)