Sleep apnoea, fatty liver, joint disease, hypertension and diabetes all improve — often faster than the weight comes off.
Improves in the majority of patients, often within months, and many stop using CPAP. The mechanism is reduced fat around the airway and lower inflammatory load — the improvement in daytime energy is usually what patients notice first.
Non-alcoholic fatty liver improves markedly, and fibrosis can regress in a proportion of patients. This is one of the strongest arguments for surgery in patients who feel otherwise well.
Every kilogram lost removes roughly four kilograms of load from the knee during walking. Patients often report joint pain improving before they consider themselves 'slim' — at 15–20 kg down.
Blood pressure, lipids and inflammatory markers all improve, and large cohort studies show reduced long-term cardiovascular mortality compared with matched non-surgical patients.
Many patients reduce or stop it, always in coordination with their own doctor rather than independently.