Research scientists predict that gastric bypass surgery to treat obesity could be a thing of the past.

They have discovered that the lower intestine could be targeted by a special food supplements which would trick the brain into thinking the stomach is full.

The treatment could save thousands of people from the trauma of an irreversible operation. It could also pave the way for revolutionary new treatment of obesity and type II diabetes within the next five years.

The research is being carried out by scientists based at the Wingate Institute for Neurogastroenterology, part of Barts and the London School of Medicine and Dentistry, Queen Mary University of London, and has been funded by the charity Bowel & Cancer Research and the Wellcome Trust.

Their findings have been published in GUT, the international journal of gastroenterology and hepatology.

Heading the team is Professor Ashley Blackshaw, Professor of Enteric Neuroscience at the Wingate.

"The difference between lean people and obese ones is that obese people ignore the signals from the small intestine that tell the brain that the body is full.

"At the moment, obese patients undergo gastric bypass surgery where they are essentially re-plumbed - undigested food bypasses the small intestine and is shunted straight to the lower bowel where it causes the release of hormones which suppress the appetite and help with the release of insulin. That makes the patient feel full and stops even the hungriest individual from eating," he said.

"We believe it's possible to trick the digestive system into behaving as if a bypass has taken place by administering specific food supplements which release strong stimuli in the same area of the lower bowel.

"It's a bit like sending a special food parcel straight to the body's emergency exit, and when it gets there, all the alarms go off."

Bypass surgery is the most effective current treatment for obesity and type II diabetes. There are rapid benefits in terms of weight loss and improvement in blood sugar levels. The National Institute of Health and Care Excellence (NICE) has just produced new draft guidelines suggesting its use could be expanded in the NHS to tackle an epidemic of type 2 diabetes.

But surgical treatments have drawbacks, including irreversibility and cost.

"What we are doing is targeting the area of the gut where that sense of feeling full begins with a capsule containing naturally occurring food supplements," said Professor Blackshaw.

"By refining those high-energy supplements and formulating them to target the lower bowel, we expect to develop a successful weight loss and anti-diabetic strategy before, and possibly in place of, bypass surgery.

"We are pursuing the opportunity to intervene directly with fatty acid, amino acid and protein sensing pathways of the lower bowel to modify endocrine responses.

"It's a totally novel idea, and we're very excited at the results so far. We are hopeful that the treatment will be widely available in NHS hospitals in the next five years."

He added that the only predicted side-effect is nausea which could be easily controlled.

Experiments were carried out on human tissue at the National Centre for Bowel Research and Surgical Innovation in Whitechapel. The next step is to find funding for substantial clinical trials.

There has been a marked increase in obesity in the UK. In 1993, 15 per cent of the population were obese. In 2011, this rose to 25 per cent.

At the same time, weight-loss surgery has increased 30-fold in the last decade. More than 8,000 operations take place annually on the NHS, and many more through private clinics.

Also called bariatric surgery, it is used as a last resort to treat people who are dangerously overweight.

It is only available on the NHS to treat people when all other treatment, including lifestyle changes, have not worked. Privately the costs are £5,000-£8,000 for a gastric band, and up to £15,000 for gastric bypass surgery.

Gastric bypass surgery is irreversible and is not a magic cure for obesity. Patients must take supplements for the rest of their lives.

Deborah Gilbert, Chief Executive of Bowel & Cancer Research, said: "We are delighted that such a significant piece of work has been supported with our funding. This is leading edge science, and as a result it can be difficult to find the financial support to push boundaries in this way.

"Not only could Professor Blackshaw's work have a major impact on the growing problem of obesity and Type II diabetes, but with the link with weight and bowel cancer clearly established, it could have even wider implications."