Being overweight or obese is associated with an increased risk for several common causes of disease and death. If current obesity trends persist, within the next two decades, it is predicted that one in 10 people will develop type 2 diabetes.6
Besides diabetes, there is an increased risk of cardiovascular problems (hypertension, stroke and coronary heart disease), a range of cancers, and musculoskeletal problems such as osteoarthritis and back pain. It can also lead to psychological problems, such as depression and low self-esteem.7,8
Obesity was a factor in 525,000 admissions to NHS hospitals in England in 2015-16. There were also were 6,438 inpatient Finished Consultant Episodes (FCEs) in NHS hospitals with a primary diagnosis of obesity and a main or secondary procedure of bariatric (weight loss) surgery.2 Obesity is also estimated to be the fourth largest risk factor contributing to deaths in England (after hypertension, smoking, and high cholesterol).9
The government estimated that the NHS spent £5.1 billion on overweight and obesity-related ill-health in 2014-15 in England. €The total cost to society is estimated to be between £27 billion and £46 billion per year,€ it said in January 2018.4  (Note that smoking has been estimated to cost the NHS £3.3 billion each year, alcohol costs £3.5 billion and physical inactivity costs £0.9 billion.6)