DoctorSpeak: Why obesity is a disease, and not a lifestyle problem

Meera, (43) a schoolteacher, has always been ‘chubby’ since childhood. Over the years, she tried all kinds of diet and fitness trends — low-carb plans, strict gym routines, intermittent fasting, juice detox/cleanses. At one point, she lost nearly 12 kg. But within a year, she regained all of it and even more. Every cycle of weight loss and regain left her more discouraged, confused and convinced that she was failing and something was “wrong” with her willpower.

Her medical history made this weight-loss struggle tougher. She had polycystic ovarian disease (PCOD) since her teenage years, developed gestational diabetes during pregnancy, and has been living with hypothyroidism for over two decades. Though her thyroid levels are well under control with medication, she continues to gain weight.

She also had a strong family history of diabetes (her father developed diabetes in his 40s) and heart disease (mother had a heart attack in her early 50s), making Meera a high-risk patient for both the diseases.

Despite a continuous struggle to overcome her medical issues by adopting a healthy lifestyle, her recent reports showed prediabetes and mildly raised triglycerides (a type of bad cholesterol) and low HDL levels (good cholesterol).

Meera’s story is the story of millions of other patients who are constantly fighting a losing battle against obesity or overweight. However, obesity is not a lifestyle problem because of overeating or a lack of willpower. It is a chronic, relapsing, multifactorial disease, recognised by the International Classification of Diseases (ICD). Except for Southeast Asia, every region of the world today has more people living with obesity than underweight.

The World Health Organisation signalled this problem as early as 1997 in its landmark report on the global obesity epidemic. In 2013, the American Medical Association officially declared obesity a disease. This decision changed how healthcare systems worldwide treat and prioritise obesity. Terming any problem a disease is not just about scientific evidence, it influences funding, policy, insurance coverage and, importantly, reduces stigma.

Behind Meera’s lifelong struggle was her medical history responsible for fluctuating hormones that further influenced her body weight, and not her lack of willpower and discipline or faulty eating habits. Because:

— PCOD leads to insulin resistance, increased hunger, fat storage and difficulty losing weight.

— Gestational diabetes signals an underlying metabolic vulnerability that continues even after pregnancy.

— Hypothyroidism, even when well controlled, slows down metabolism and makes weight management difficult.

— Hormones such as insulin, cortisol, ghrelin and leptin affect appetite, satiety, cravings, fat storage and energy use. When these hormones are imbalanced, the body naturally tends to gain weight and resist weight loss.

This is why obesity cannot be simplified to “eat less, move more”. It is a biological condition influenced by genetics, hormones and environment.

Unfortunately, society still blames individuals. People are told they lack discipline, that they simply need stronger willpower. But research shows that obesity is shaped heavily by our environment — from the availability of ultra-processed foods, to marketing strategies, to long work hours affecting the body’s circadian rhythm, to the lack of safe spaces for physical activity. When the surrounding system is designed to promote overeating and reduce activity, personal effort alone cannot overcome it.

This blame leads to weight stigma, a harmful reality faced by many like Meera. People with obesity are judged, stereotyped and dismissed, sometimes even by healthcare providers. This stigma increases stress, worsens emotional eating and delays treatment. It harms physical and mental health.

Another important piece of the puzzle is how people respond differently to food cues. Some experience constant ‘food noise’, intrusive thoughts about food, strong cravings and difficulty controlling portions. This makes their journey much harder than it appears to.

Lifestyle change is the first step in managing obesity. Reducing daily calorie intake by around 500 calories and adding 20–30 minutes of regular activity can improve many health markers. However, it is important to note that for a large number of patients like Meera, this may not be enough as there are many other medical factors at play. The body naturally reacts to weight loss with increased hunger, reduced or slow metabolism and compensatory behaviours — mechanisms that evolved to protect us from starvation. These biological responses explain why weight regain is so common and why short-term diets often fail.

This is why modern obesity treatments are focusing on long-term medical care, and not temporary fixes. New anti-obesity medications reduce hunger, improve satiety, reduce ‘food noise’ and make sustained weight loss possible. Earlier, losing and maintaining more than 10 per cent of body weight typically required surgery. Today, medications offer realistic, long-term alternatives for many.

Importantly, we must move beyond BMI as a marker of obesity. People having the same BMI can have different metabolic health parameters. A balanced and complete assessment looks at physical, psychological and functional health. Identifying different types of obesity helps personalise treatment — whether lifestyle therapy, medication, surgery or a combination of treatments is needed.

Obesity management requires teamwork: doctors, dietitians, physiotherapists, psychologists, coaches and surgeons working together to support long-term success.

Even a modest 5–10 per cent weight loss over six to 12 months can reduce the risk of diabetes, improve blood pressure and cholesterol, and boost energy levels. Larger weight loss brings even bigger benefits — better heart health, improved liver function, reduced sleep apnoea and less joint pain.

Preventing weight regain remains the biggest challenge. Regular follow-ups, identifying triggers, ongoing counselling and adjusting treatment plans help people maintain progress.

For Meera, the turning point came when she understood that obesity is not her fault, and it is not a battle she has to fight alone. With proper medical care, hormonal evaluation, long-term support and evidence-backed treatment, she finally has a plan that works with her body, not against it.

Her journey is a reminder that obesity is a disease — one that deserves scientific treatment, compassionate care and zero judgement.

— The writer is Senior Endocrinologist, and Founder, SWEET Diabetes Foundation

Factcheck: Approximately one in four Indian adults is overweight or obese, 1 in 10 has diabetes and 1 in 3 has abdominal obesity. According to the National Family Health Survey-5 (2019-2021), around 24 per cent of women and 23 per cent of men are obese. There has been a rise in overweight children, with the percentage of children under five who are overweight increasing from 2.1 per cent in NFHS-4 (2015-16) to 3.4 per cent in NFHS-5 (2019-21). Obesity and related chronic diseases are already costing the country an estimated $28.9 billion every year.