Who can have weight loss surgery? 

Weight loss surgery is only recommended for people with a body mass index (BMI) of 40 or more, or a BMI of 35-40 and a serious health condition that could be improved if you lose weight, such as type 2 diabetes or high blood pressure.

The National Institute for Health and Care Excellence (NICE) also recommends that weight loss surgery should only be offered on the NHS if all the following conditions apply:

  • You've tried all the appropriate non-surgical methods, such as diet and exercise, but failed to achieve or maintain a beneficial level of weight loss.
  • You've been receiving or will receive intensive management from a multidisciplinary team of specialists led by a clinician  see getting ready for surgery.
  • You agree to commit to long-term follow-up treatment after surgery at a specialised obesity service.
  • You're fit and healthy enough to withstand anaesthesia and surgery.

Read the full NICE guidelines on identification, assessment and management of overweight and obesity in children, young people and adults.

There may be slightly different criteria with your local clinical commissioning group (CCG), which could affect your access to surgery.

Type 2 diabetes

People who have recently been diagnosed with type 2 diabetes may be considered for an assessment for weight loss surgery if they have a BMI of 30-34.9.

This may only be considered as long as they've been receiving or will receive intensive management from a multidisciplinary team of specialists led by a clinician.

When weight loss surgery isn't suitable 

Weight loss surgery may not be recommended if you have a serious illness that would not be improved after the operation, such as:

Weight loss surgery is also unlikely to be recommended if a mental health condition or other underlying factor means you'd be unable to commit to long-term follow-up and lifestyle changes.

Examples include:

  • schizophrenia for which you are refusing to seek treatment 
  • actively abusing alcohol or drugs
  • a previous history of not complying with medical recommendations about your care


Weight loss surgery would only be considered to treat obese children in exceptional circumstances, and only if the child is physically mature (around the age of 13 for girls and 15 for boys).

Most experts in obesity would only recommend surgery as a last resort treatment for children who are severely morbidly obese (a BMI of 50 of above), or who are morbidly obese (a BMI of 40 or above) and also have a serious health condition that would improve if they lost weight.

Read the NICE guidelines on managing overweight and obesity among children and young people.

Page last reviewed: 26/03/2015

Next review due: 26/03/2017