Your web browser is outdated and may be insecure

The RCN recommends using an updated browser such as Microsoft Edge or Google Chrome

feet on weighing scales

Obesity

Obesity is a major cause of ill health in the UK. Nursing and midwifery staff have a key role in supporting people to maintain a healthy weight. 

Obesity is a growing concern across the UK. In 2022, results of an analysis published by Cancer Research UK estimated that more than 21 million UK adults will be obese by 2040. This is equivalent to almost 4 in 10 of the UK adult population (36%).

Additionally, the costs relating to obesity across the UK is projected to reach £9.7 billion by 2050.

It is difficult to assess the specific effect of obesity on mortality and morbidity, however, we do know that it is a contributory risk factor to general morbidity and premature death.

Definition of obesity

The World Health Organization's definition of obesity is a Body Mass Index (BMI) greater than or equal to 30.

The BMI is the most used measure for adults in the UK. It is the same for both sexes and across all ages and as such provides the most useful population-level indicator of overweight (BMI of 25 or above) and obesity. 

However, it should only be used as a guide and does not account for muscle mass or for fat distribution which varies between individuals. In children and adolescents, the British 1990 growth reference charts are used to classify the weight status of children according to their age and sex because the BMI will vary depending on these factors.

The NHS provides a useful tool for measuring obesity.

Health problems associated with morbid obesity may include: 

  • hypertension
  • heart disease
  • raised cholesterol levels
  • type 2 diabetes
  • respiratory problems
  • gastroesophageal reflux
  • urinary stress incontinence
  • degenerative arthritis
  • cancer
  • skin infections
  • sleep disturbance
  • infertility.

There are also serious psychological and social repercussions from being overweight or obese. 

From April 2013, local responsibility for the prevention and management of obesity in England transferred to local authorities.

Useful resources

England

Scotland

Wales

Northern Ireland

Public health NICE guidance

RCN resources

Other resources

Page last updated - 17/07/2024