Why obesity is not simply about willpower

For many people living with obesity, one of the toughest challenges is not just losing weight – it is living with the belief that struggling to do so reflects a lack of discipline or willpower.

Today, science tells a different story. Obesity is increasingly recognised as a chronic disease shaped by biology, genetics and the environment, said adjunct associate professor Sue-Anne Toh, a senior consultant endocrinologist and co-founder, CEO and medical director of Novi Health.

“This shift is important because it helps explain why many individuals struggle despite their best efforts and why effective management often requires a more comprehensive, medically supported approach,” she added.

THE SCIENCE BEHIND OBESITY

According to Prof Toh, body weight is regulated by a complex interplay of hormones, the brain and metabolism. In people living with obesity, this network can become disrupted, making it harder to regulate hunger, fullness, and how the body uses and stores energy.

“I often see patients who experience persistent hunger, even after eating, or who do not feel full in the same way others might,” she explained. “There can also be changes in how the brain responds to food, making it feel more rewarding and increasing the drive to eat.”

At the same time, the body may conserve energy more efficiently, meaning it burns fewer calories for the same level of activity. “These are not simply issues of behaviour or choice,” Prof Toh emphasised. “This dysregulation is a key reason why many individuals find it difficult not only to lose weight, but also to maintain that weight loss.”

WHY LONG-TERM MANAGEMENT MATTERS

Left untreated, obesity can increase the risk of serious health conditions, including type 2 diabetes, cardiovascular disease, hypertension, fatty liver disease, obstructive sleep apnoea and certain cancers. It can also reduce quality of life through reduced mobility, joint pain, fatigue and poorer mental well-being.

Understanding obesity as a chronic disease changes how it should be managed. Like diabetes or hypertension, it requires ongoing care rather than short-term solutions.

When someone loses weight, the body does not necessarily interpret it as progress. Instead, it may perceive weight loss as a form of stress – or even starvation – and respond by trying to restore the lost weight. “Hormones that stimulate hunger tend to increase while hormones that signal fullness may decrease. At the same time, the body’s metabolic rate often slows,” said Prof Toh. This makes maintaining weight loss much harder – even for people who eat well and exercise regularly.

Viewing obesity through this lens helps shift the conversation away from blame and towards compassionate, evidence-based care. It also encourages patients to move beyond quick fixes, recognising that the condition requires long-term management.

HOW OBESITY TREATMENT HAS EVOLVED

A common misconception is that obesity treatment begins and ends with diet and exercise. “While these remain important, we now have a much better understanding of obesity and a wider range of evidence-based treatments, including medications and multidisciplinary care,” said Prof Toh.

Earlier generations of weight-loss medications primarily worked by suppressing appetite or reducing fat absorption. While some patients benefited, these treatments generally produced modest weight loss and, in some cases, side effects that limited their long-term use.

Scientific advances have led to newer treatment options. Originally developed for diabetes, glucagon-like peptide-1 (GLP-1)-based medicines were later found to support weight loss by mimicking a naturally occurring hormone that signals fullness, slows stomach emptying and reduces food cravings.

Newer GLP-1-based medicines have been developed specifically to target obesity. When combined with lifestyle and behavioural support, they can help patients achieve greater and more sustained weight loss.

THE NEXT STEP IN OBESITY CARE

Researchers have continued to advance the understanding and treatment of obesity. Newer therapies include medicines that act on two hormone pathways – GLP-1 and glucose-dependent insulinotropic polypeptide (GIP).

“Activating both pathways together allows us to address weight regulation from two complementary angles: appetite control (GLP-1) and metabolic function (GIP),” said Prof Toh. “This can lead to more pronounced effects on weight loss and metabolic health.”

However, she stressed that no single intervention is a complete solution. “Sustainable weight management requires a comprehensive approach that combines medical treatment with nutrition, physical activity and behavioural strategies such as mindful eating, meal planning and addressing emotional eating triggers. The goal is not just short-term weight loss but helping patients build habits that support their health in the long run.”

Equally important, Prof Toh hopes greater understanding of obesity will reduce the stigma surrounding it, so that more people feel comfortable speaking to a healthcare professional.

“Seeking help is not a sign of failure – it is a proactive and crucial step towards better health,” she said. “With the right support and personalised approach, obesity can be managed effectively, just like any other chronic condition.”

If you are concerned about your weight, speak to a healthcare professional to explore a personalised long-term management plan. Learn more at letstalkweight.sg.

This article is intended for general educational purposes only and does not constitute medical advice. Individuals should consult a qualified healthcare professional for diagnosis or treatment recommendations.
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