Citerank: (14) 369907NICE Guidance on Diet, Nutrition and ObesityNote: extended excerpts from National Institute for Health and Care Excellence are included and cross-linked here to help explore and understand their intersection with the policy space and their implications. Those seeking specific guidance should refer to the full Guidelines and Pathways directly.565CA4D9, 369908NICE – DietHaving a healthy balanced diet helps prevent obesity, cardiovascular and many other conditions. This pathway covers recommendations for everyone about diet and lifestyle, and recommendations for health professionals on interventions to encourage people to follow a healthy diet.565CA4D9, 369912NICE – ObesityGuidelines on preventing and managing obesity.565CA4D9, 369929NICE – Healthcare professional interventionsInterventions by healthcare professional to address obesity.565CA4D9, 370041NICE – Increasing physical activity565CA4D9, 370042NICE – Changing diet565CA4D9, 370046NICE – Interventions with drug treatment Consider pharmacological treatment only after dietary, exercise and behavioural approaches have been started and evaluated.565CA4D9, 370047NICE – Interventions to change behaviour565CA4D9, 370048NICE – Interventions to increase physical activityEncourage adults to increase their physical activity even if they do not lose weight as a result, because of the other health benefits physical activity can bring (for example, reduced risk of type 2 diabetes and cardiovascular disease). Encourage adults to do at least 30 minutes of moderate or greater intensity physical activity on 5 or more days a week. The activity can be in 1 session or several sessions lasting 10 minutes or more.565CA4D9, 370049NICE – Interventions to change diet565CA4D9, 370050NICE – Surgical interventions for obese adults565CA4D9, 370057Reduce calorie intake for adults who are obese565CA4D9, 371177NICE – Preventing cardiovascular disease565CA4D9, 399912Assessing health risk and interventionThe latest guidance from the National Institute for Health and Care Excellence on the assessment of the health risk arising from obesity and associated interventions. 82AECCD8

Assessing the body mass index (BMI) of children is more complicated than for adults because it changes as they grow and mature. In addition, growth patterns differ between boys and girls.

Thresholds that take into account a child's age and sex are used to assess whether their BMI is too high or too low. These are usually derived from a reference population, known as a child growth reference, with the data presented in BMI centile charts. In a clinical assessment, a child or young person on or above the 98th centile is classified as obese. A child or young person on or above the 91st centile, but below the 98th centile, is classified as overweight. [Note: Several classification systems are used in the UK to define 'obesity' and 'overweight' in children. In the analysis of population surveys such as the National Child Measurement Programme and the Health Survey for England (HSE), children over the 85th centile, and on or below the 95th centile, are classified as being 'overweight'. Children over the 95th centile are classified as being 'obese'. However, the NCMP uses the clinical cut-off points described above when providing feedback about the BMI of individual children to parents and carers.]

When monitoring and comparing groups of children and young people BMI zscores may be used. BMI z score is a measure of how many standard deviations a child or young person's BMI is above or below the average BMI for their age and gender. (This is based on a reference population known as a child growth reference.) For instance, a z score of 1.5 indicates that a child is 1.5 standard deviations above the average value, and a z score of -1.5 indicates a child is 1.5 standard deviations below the average value.

The advantage of using BMI z scores, instead of BMI, is that it allows direct comparison of BMI (and any changes in BMI) across different ages and by gender. This term is sometimes used interchangeably with 'BMI standard deviation score' (BMI SDS).