Updated NICE Guidelines on Obesity Management

The 2025 guideline consolidates and replaces several previous documents including Obesity: identification, assessment and management (CG189, November 2014) – streamlining recommendations into a single, comprehensive resource.

The emphasis is clear: obesity is a complex, chronic condition requiring ongoing, tailored support.

Key updates include:

• Recognition of several factors: Before initiating discussions, clinicians are encouraged to consider several factors such as genetics, environment, comorbidities, socioeconomic status, ethnicity, trauma history, and neurodiversity.
• Permission-based conversations: Asking if a person is open to discussing weight is now a formal recommendation. If declined, the choice must be respected without judgment.
• Non-stigmatising language: Terms like “living with obesity” are preferred over labels. Clinicians should identify and use the person’s preferred terminology.
• Contextual sensitivity: Weight discussions should only occur when appropriate to the appointment’s purpose, and clinicians should reflect on their own biases before engaging.

For frontline staff, these changes mean:

• More thoughtful assessments: Weight history, medication effects, and psychosocial factors must be considered before recommending interventions.
• Multidisciplinary collaboration: Especially for children and young people, coordinated care involving dietitians, psychologists, and educators is essential.
• Documentation and continuity: Outcomes of weight-related discussions should be recorded to support continuity across care teams

Body Mass Index (BMI) Classification Updates

It is recommended that BMI should be considered alongside waist circumference and overall health status, especially for ethnic minority groups.

Updated BMI Classifications

• Healthy weight: BMI 18.5 kg/m2 to 24.9 kg/m2
• Overweight: BMI 25 kg/m2 to 29.9 kg/m2
• Obesity class 1: BMI 30 kg/m2 to 34.9 kg/m2
• Obesity class 2: BMI 35 kg/m2 to 39.9 kg/m2
• Obesity class 3: BMI 40 kg/m2 or more.

People with a South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background are prone to central adiposity and their cardiometabolic risk occurs at a lower BMI, so use lower BMI thresholds as a practical measure of overweight and obesity:

1. Overweight: BMI 23 kg/m2 to 27.4 kg/m2
2. Obesity: BMI 27.5 kg/m2 or above.

For people in these groups, obesity classes 2 and 3 are usually identified by reducing the thresholds by 2.5 kg/m2.

Encourage adults with a BMI below 35 kg/m² to measure their own waist-to-height ratio to assess central adiposity.

Measure

Find the bottom of the ribs and the top of the hips.

Wrap a tape measure around the waist midway between these points (this will be just above the belly button) and breathe out naturally before taking the measurement.

Calculate

Measure waist circumference and height in the same units (either both in centimetres, or both in inches). If you know your height in feet and inches, convert it to inches (for example, 5 feet 7 inches is 67 inches).

Divide waist measurement by height measurement. For example:

• 38 inches divided by 67 inches = waist-to-height ratio of 0.57 or
• 96.5 cm divided by 170 cm = waist-to-height ratio of 0.57.

Beyond respectful conversations, delivering safe, effective, and compassionate care for persons of a larger size requires the right skills and equipment.

At Five, we specialise in seating and plus size patient care – supporting healthcare teams with tailored equipment solutions and CPD-certified Manual Handling training. Click here to learn about our Plus Size Patient Manual Handling CPD or here to learn about our Advanced HALO CPD.

Sources:

https://www.nice.org.uk/guidance/ng246/chapter/Identifying-and-assessing-overweight-obesity-and-central-adiposity

https://www.nhs.uk/health-assessment-tools/calculate-your-body-mass-index/calculate-bmi-for-adults