NICE criteria for weight-loss medicines, explained plainly

Body mass index is a rough screening tool, calculated from height and weight. NICE uses it with other information because on its own it does not describe health. The criteria aim to direct limited NHS resources to people who are most likely to gain medical benefit, such as a lower risk of diabetes, heart disease or joint problems.

This is why people sometimes find that they sit just below the threshold and cannot access NHS treatment, while someone else with a slightly higher number can. The line is a pragmatic funding rule, not a statement about who deserves care.

Both appraisals refer to weight-related health conditions. These generally include problems where excess weight raises risk or worsens control, and the lists used by services commonly cover:

• Impaired glucose regulation, prediabetes or type 2 diabetes.

• High blood pressure.

• Dyslipidaemia (abnormal blood fats).

• Obstructive sleep apnoea.

• Cardiovascular disease.

• Significant osteoarthritis affecting mobility.

NICE obesity guidance recognises that health risks from excess weight appear at lower BMI levels in people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background. Clinicians are advised to use lower BMI thresholds for these groups when deciding who to assess or refer. If you belong to one of these groups and are told you do not qualify, it is reasonable to ask whether adjusted thresholds were applied.

The semaglutide appraisal places treatment in specialist weight-management services, where people are usually supported for a limited period rather than indefinitely. The tirzepatide appraisal allows prescribing in primary care or specialist services depending on local arrangements. Local commissioners decide how and when these pathways open, which explains why access differs between areas.

On the NHS, continuing treatment generally depends on showing adequate response within a defined period. If the response is not enough, the recommendation is to stop. Services also review side effects and whether the person remains engaged with the supporting programme. Ask at the start what the review points are and what counts as a satisfactory response.

Not meeting NICE criteria does not mean you have no options. You can ask your GP about structured behavioural programmes, dietetic support, treatment for conditions such as sleep apnoea or high blood pressure, and the older weight-management medicine orlistat. Some people consider private assessment. A private prescriber who offers a medicine at a BMI below the licensed threshold is making an off-licence decision and should explain the reasoning and the limits of the evidence.