The World Health Organisation and many national health services have recognised obesity as a disease. In the UK, in order to prevent secondary diseases resulting from obesity, the NHS does pay for surgical treatment in some cases.

Obesity leads to type II diabetes, to high blood pressure, angina, heart attacks, strokes, bowel cancer, arthritis, sleep apnoea, sterility and miscarriage or stillbirth. Obesity shortens life – it leads to premature death. However, if obese people manage to lose a lot of weight, they can considerably reduce their risk of health problems.

Type II diabetes can be regulated simply by losing weight. Obesity creates serious health risks, with increased risk of high blood pressure, type II diabetes, and joint problems. Certain types of cancer can also be caused by obesity – for example, the risk of breast cancer is increased by 50%. Cholesterol levels rise, and the risk of gall bladder problems increases. Respiratory problems can develop, as can coronary disease. The more excess weight carried, the higher the risk of health problems. Life expectancy is considerably reduced.

Obesity reduces mobility – although more exercise is exactly what is most needed. Obesity also makes existing medical problems worse. It also reduces fertility and thus the chance of getting pregnant; if obese women do get pregnant, they sometimes have problems giving birth.