Weight loss surgery: Up to two million could benefit
Up to two million people in England could be eligible for weight loss surgery, experts say.
Bariatric surgery, such as fitting gastric bands, can cut the fatal risks from obesity-related problems such as heart disease and Type 2 diabetes.
Although it has been growing in popularity, only 8,000 people a year are currently receiving the treatment.
Researchers from Imperial College London believe more than 5% of the adult population would qualify for it.
However, they acknowledge that if it were carried out in such huge numbers it would have significant financial implications for the NHS.
What is bariatric surgery?
Bariatric surgery, also known as weight loss surgery, is used as a last resort to treat people who are dangerously obese and carrying an excessive amount of body fat.
This type of surgery is only available on the NHS to treat people with potentially life-threatening obesity when other treatments haven't worked.
This is defined as:
- Having a body mass index (BMI) of 40 or above or having a BMI of 35 or above plus another serious health condition such as type 2 diabetes or high blood pressure.
The two most common types of weight loss surgery are:
- Gastric band, where a band is used to reduce the size of the stomach so a smaller amount of food is required to make someone feel full
- Gastric bypass, where the digestive system is re-routed past most of the stomach so less food is digested to make someone feel full
Depending on the complexity of the procedure and the care required after surgery, NHS England says bariatric surgery costs can vary between £3,000 and £11,505.
Gastric band surgery is cheaper than gastric bypass surgery, which is a more complicated and risky operation.
Guidelines recommend that bariatric surgery be offered to the morbidly obese and those who are not quite morbidly obese but already have other problems, such as heart disease and high blood pressure.
Researchers tested how many were actually eligible by looking at the health of nearly 9,500 people, the Journal of the Royal Society of Medicine reported.
Lead researcher Dr Sonia Saxena said: "Despite clear guidelines outlining who can undergo such surgery with the NHS, and evidence that these procedures are cost-effective in the long run, less than 1% of those eligible have weight loss surgery each year.
"This raises questions about why more procedures are not currently being carried out."
The researchers said there were several reasons why the rates of surgery were so low.
One theory was that the socio-economic groups most likely to need the treatment - the lowest ones - were the ones who made the least use of healthcare services.
The researchers said another barrier was that people might be struggling to make the lifestyle improvements required before having surgery.
Access to treatment may also be being restricted as budgets are squeezed.
While the numbers having the surgery have increased threefold in five years, there was actually a small dip in patients last year.
Tam Fry, of the National Obesity Forum, said: "The failure to provide appropriate bariatric surgery is a disgrace, the worse so since the surgery pays for itself in two to three years."
An NHS England spokesman said many other clinical factors contribute to the decision whether to proceed with bariatric surgery "which have not been taken into account" in the research paper.
The NHS Choices website says that most people with a gastric band can expect to lose around half their excess body weight, whereas most people with a gastric bypass will lose around two-thirds of the excess body weight.
A gastric bypass carries a higher risk of complications, including death, because it is a more difficult operation.
The risk of any sort of complication after gastric band surgery is around 1 in 10 compared to 1 in 5 for gastric bypass surgery.
The risk of death after a gastric band is around 1 in 200 compared to 1 in 100 for a gastric bypass.