Obesity Information

Obesity is a complex condition where excess weight has a negative impact on someone’s physical and psychological health. Excess weight also has an overall impact on someone’s well-being and mobility.

The World Obesity Atlas 2024, published by the World Obesity Federation, predicts that 1.25 billion people globally will be living with obesity by 2030.

Worldwide, at least 2.8 million people die each year because of being overweight or having obesity. Furthermore, an estimated 35.8 million (2.3%) of global DALYs are caused by overweight or obesity [1].

DALYs stands for Disability-Adjusted Life Years, which is a measure of overall disease burden, expressed as the number of years lost due to ill-health, disability, or early death. It is used to assess the impact of different diseases and injuries on a population and to prioritise health interventions.

Dr Andrew JENKINSON: Prevalence of Obesity

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So why has obesity become so much more prevalent in the last 20 or 30 years? I think the answer to this stems all the way back to the 1980s, when the FDA encouraged people to eat less saturated fat and people naturally started to eat more grains, refined carbohydrates. And we know that refined carbohydrates and sugar block the weight-regulating hormone leptin that normally keeps us slim and causes parts of the population to really suffer with obesity. And I think the fact that we’ve moved onto a diet quite high in carbohydrates has directly caused obesity.

Related Diseases

Diseases and health conditions that are commonly linked to obesity include:

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To diagnose obesity, a healthcare professional will take measurements of a person’s height and weight to determine their body mass index (BMI). They may also measure waist size and ask about activity levels and psychological well-being.

A BMI score of more than 30 and a waist size of more than 102cm (40 inches) for men or 88cm (34.5 inches) for women usually indicates a diagnosis of obesity. However, these measurements change depending on someone’s ethnicity.

A consensus statement (December 2023) from the International Obesity Collaborative [2] says Body mass index (BMI) is a measure used to screen for obesity that neither defines the disease nor replaces clinical judgment. Social determinants, race, ethnicity, and age can modify the risk associated with a given BMI. Successful obesity management should be measured by the health and quality-of-life goals established through shared decision-making by the patient and their healthcare provider rather than changes in BMI alone.”

Causes of obesity

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There are many complex factors that contribute to obesity. Contrary to many misheard beliefs, many of them are difficult or impossible to control.

For example, the hypothalamus is a part of the brain that triggers signals to make you feel hungry and full. The strength and frequency of those signals are things you can’t control.

Genetics can also make you more likely to gain weight, with genetic factors contributing to an estimated 40-70% of variation in body weight.

Similarly, hormones from the gut play a key role in regulating body weight, and disruption of those hormones can lead to obesity.

These factors can also cause people to regain weight after losing it.

Treatment for obesity

Obesity care and weight loss are not the same. Obesity care delivered by qualified clinicians consists of evidence-based options that address comorbidities of obesity (diabetes, hypertension, hyperlipidemia, etc.) and improve well-being.

Obesity care is about health, not weight. Weight loss is just one outcome of obesity care.

Obesity is a serious, relapsing chronic disease that requires long-term care, just like any other chronic disease. Safe and effective evidence-based obesity treatments that improve patient health are available.

Evidence-based treatments for obesity and severe obesity may include: nutrition and behaviour modification, physical activity, medications, approved devices, and metabolic/bariatric surgery.

In decisions shared with patients, clinicians utilise one or more of these modalities to treat obesity.

A consensus statement (December 2023) from the International Obesity Collaborative points out that globally, medical coverage limits access to effective obesity care, to the detriment of patient health.

“National statutes and medical insurance coverage have not kept pace with evidence and advances in clinical science. Like other serious chronic diseases, support for obesity care must be incorporated into national public health strategies and include standard benefits and coverage for obesity across the lifespan. People with obesity deserve care, free from stigma and shame,” it says.

Healthcare professionals can help to treat obesity by prescribing changes in behaviour, medication, or surgery.

Very broadly, behavioural change treatment interventions can help people lose about 5% of their bodyweight.

Adding medication to these changes can help people lose about 10% to 15% of their bodyweight, but it is important to understand that stopping medication increases the risk of weight returning to pre-treatment levels, and any medication must be continued long-term.

Surgery can treat those who have significant weight to lose with many losing about 25- 35% of their body weight within 12 months.

Surgery can also help alleviate health conditions such as high blood pressure, type 2 diabetes, and sleep apnea.

Patients should ask their doctor to see if they qualify for a referral to a specialist centre for treatment.

A new AI driven web-tool developed by the University of Lille and supported by the SOPHIA project now allows patients and their doctors to accurately predict weight loss over five years following different types of bariatric surgery

For more information please see:

Prof Bart Van der Scheuren MD, PhD: The Teatment of Obesity

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I think in terms of treatment for obesity it’s not about one size fits all. I think that’s very important for each person living with obesity to understand. Each person with obesity is different, the reasons why he developed the disease are different and the answers and the treatments can therefore also be different.

The first thing is to assess what the overweight means in each individual case and then to adapt the treatment in a personalized tailored way to the patients and that treatment will be different in an adolescence than someone who is in his adult age or even at older age. The treatment must be adapted to the person and otherwise it will not be successful.

Addressing Obesity


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I’m Pieter Gouffacombe, I’m the Deputy General Administrator of the National Institute for Health and Disability Insurance in Belgium. The big challenge we have at policy level with obesity is that we know the figures, so we know that we already have a significant number of people dealing with overweight and obesity and we know that this will grow, so we should prepare to have better care, but also to have better prevention and to also look at overweight and obesity not only as a problem of the care system, but of society as a whole. The big problem we face is that obesity is still a little bit looked at as a sort of responsibility of the person and you’re blamed for being overweight or having obesity and we know from evidence that in fact it’s a complex interplay of a lot of different factors, genetic factors, hormonal factors, also social factors and of course also behavior of persons that can cause overweight and obesity and if you really want to tackle the obesity challenge in a fundamental way, then we need to acknowledge that this won’t be by only blaming the victim.

Well, science is one part of the solution of course. The whole discussion we have for the moment on the medicines that could help control overweight and obesity and as a payer, the National Institute is a payer in health insurance, we are looking forward to the discussions we will have on the value, but also on the price of these products, so we see that innovation and scientific new insights of course will come up with new solutions. That said, we should also take into account that part of the solution is also in the organization of the care system, for example the collaboration between the primary care, also the more specialized care in hospitals and even tertiary care, so we should in fact capitalize on the new insights that science brings, but we should also work on the organization of our care system.

From a Belgian perspective and knowing what our strengths and our weaknesses are, my big dream would be that the next governments, and we will have elections for the national, regional and local governments during this year, that these governments would really set an ambitious objective with regard to healthy lifestyle and obviously healthy food, healthy eating, also sports etc. and tackling in a preventive way also overweight and obesity would be clearly one target in that, but we should in some way find a partnership between governments, between non-profit organizations, between patients and citizens, also with industry to really come together and fight the challenges we have with regard to overweight and obesity.

The growing precedence of obesity is also becoming an increasing concern for policymakers. They are realising they have a big challenge ahead of them. Pedro Facon, Deputy General Administrator of the Belgian National Institute for Health and Disability Insurance (RIZIV-INAMI-NIHDI) explains.

Further information on obesity

When searching for reliable sources of scientific and medical information on obesity, it’s essential to rely on reputable websites and organisations. Here is a selection:

The World Health Organization

The European Association for the Study of Obesity (EASO)

The European Coalition for People living with Obesity (ECPO)

British Obesity & Metabolic Surgery Society (BOMSS)

Obesity UK


World Obesity Atlas 2022

OECD data and reports

Eurostat statistics Overweight and Obesity – BMI statistics

Always cross-reference information and consult healthcare professionals when making decisions related to obesity prevention, management, or treatment. Reliable websites often link to scientific studies and medical guidelines, making them excellent starting points for in-depth research on obesity-related topics.

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[1] From <https://www.who.int/data/gho/data/themes/topics/topic-details/GHO/body-mass-index

[2] International Obesity Collaborative Members include the Obesity Action Coalition, OAC; the American Society for Metabolic and Bariatric Surgery, ASMBS; the European Association for the Study of Obesity, EASO; EatRight; The Global Obesity Patient Alliance, GOPA; Obesity Canada; the Obesity Medicine Association; SOPHIA, the Stratification of Obesity Phenotypes to Optimize Future Therapy; the Strategies to Overcome and Prevent Obesity Alliance, STOP; The Obesity Society; the European Coalition for People living with Obesity, ECPO; and the Korean Society for the Study of Obesity, KSSO.

“In the EU, it is estimated that over 200 million adults may be overweight or obese – that is over half the adult population.”


European Commission

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