For many years, obesity has been discussed as if it were simply a question of willpower: eat less, move more, try harder. But doctors are increasingly moving away from that view. We now know that obesity is a complicated, chronic medical illness that is affected by biology, hormones, genetics, metabolism, psychology and the environment in which people live. That shift moves the conversation away from blame and toward treatment.
Across the UK, obesity is now one of the most urgent public health issues: In England, the latest Health Survey for England reported that 66% of adults were overweight or living with obesity in 2024, while 30% were living with obesity. In Scotland, the 2024 Scottish Health Survey found that 31% of adults were living with obesity, up from 24% in 2003.
Obesity is strongly linked with type 2 diabetes, cardiovascular disease, high blood pressure, sleep apnea, joint problems, fatty liver disease and some cancers. It also affects mobility, confidence, mental wellbeing and everyday quality of life.
For Assoc. Prof. Dr. Nadir Adnan Hacim, an Obesity and Metabolic Surgery specialist at Erdem Hospital, the most important change is that patients are no longer seen as people who have “failed.”
“Obesity is not simply a matter of choice or discipline,” says Dr. Hacim. “It is a chronic medical condition in which genetics, hormones, metabolism and environment all interact. When we accept that, we can stop blaming patients and start treating them properly.”
The body fights weight loss
Research has shown that hormonal changes after weight loss can continue long after the diet itself has ended. In simple terms, the body may push the person back towards their previous weight. That is one reason doctors now describe obesity as a chronic and relapsing condition, rather than a short-term lifestyle problem.
“Many patients come to us after years of dieting, and they feel ashamed because they believe they have failed,” says Dr. Hacim. “But often, what they are experiencing is the body’s defence system. After weight loss, the body may increase appetite and slow metabolism. That is why long-term treatment must be planned medically.”
Genetics also influence weight. Studies have shown that body weight is partly controlled by brain pathways involved in hunger, reward and energy balance. Hormones involved in appetite and fullness, including leptin, ghrelin, insulin and GLP-1, all play a role as well.
Treatment is moving beyond diet and exercise
Recognising obesity as a disease does not mean ignoring lifestyle. Nutrition, physical activity and behavioural support remain important. But for many patients, especially those with severe obesity or related health conditions, they may not be enough on their own.
GLP-1 and GIP-based medicines have made the biology of obesity more visible to the public. These treatments work on appetite and fullness pathways, helping some patients reduce food intake and improve metabolic health. National Institute for Health and Care Excellence (NICE) recommends tirzepatide for eligible adults with obesity or overweight and at least one weight-related condition, alongside reduced-calorie diet and increased physical activity.
For selected patients, bariatric or metabolic surgery may also be considered. Procedures such as sleeve gastrectomy and gastric bypass do more than reduce stomach size. They can influence hunger hormones, fullness signals, blood sugar control and insulin sensitivity. This is why many specialists now use the term “metabolic surgery” because the aim is not only weight loss, but better health.
“Whether we are discussing medication or surgery, the principle is the same,” says Assoc. Prof. Dr. Hacim. “The right treatment must be matched to the right patient. There is no single solution for everyone, and there should never be pressure.”
For optimum results, patients need more than a procedure or prescription. They need careful assessment, clear explanations, realistic expectations, follow-up support and a team that understands how emotional the journey can be.
Erdem Hospital’s approach is built around making that journey feel organised, safe and human. The staff offers a holistic approach to ensure the comfort and care of all patients. It takes pride in focusing on making a difference in patients’ quality of life, not just the “before and after” story.
“When a patient feels understood instead of judged, treatment becomes possible,” says Dr. Hacim. “Our responsibility is to explain the science, offer safe options and walk beside the patient through the process.”
