Body weight is influenced by more than willpower alone. Diet and activity levels play an important role, but so do hormones, genetics, sleep patterns, stress levels and certain medical conditions. Carrying excess weight is linked to an increased risk of type 2 diabetes, high blood pressure, heart disease, sleep apnoea, joint problems, fatty liver disease, and some cancers.

According to the NHS, obesity is considered a long-term health condition. Like other chronic conditions, it may require ongoing management. For some individuals, changes to diet and exercise do not lead to enough weight loss on their own — in these cases, treatment may be considered as part of a structured, medically supervised plan.