Obesity: Look beyond body weight
Obesity is a global problem that has increased alarmingly over the past 30 years. Obesity arises from a complex interplay of biological, psychological, behavioural and environmental factors. As such, it is not simply the result of eating too much and exercising too little.
Research on obesity
Fascination with adipose tissue
The increase in the number of people with overweight and obesity worries him, not only because obesity is often associated with a lower quality of life, but also because this increases the pressure on healthcare. Professor Goossens focuses his research on biological factors that contribute to the occurrence and maintenance of obesity and related cardiometabolic health problems, as well as interventions to improve overall health in overweight and obese people.
Adipose tissue plays an important role here. Goossens developed his fascination with adipose tissue during internships as a master's student in the Department of Human Biology at Universiteit Maastricht and then at the University of Oxford (UK). ‘Fat is much more than just a passive store of excess calories; it is an active organ that is essential for our metabolism and health. When something goes wrong in this tissue, it can lead to serious diseases such as type 2 diabetes, cardiovascular disease and even cancer. The importance of proper functioning of adipose tissue has long been underestimated,’ says Goossens.
Impairments in adipose tissue function in obesity
Adipose tissue plays a crucial role in our body. Goossens: ‘If fat cells become overloaded, it becomes increasingly difficult for them to store extra calories. I sometimes compare it to a balloon; one can only inflate it up to a certain point. Those larger, overloaded fat cells function less well. The excess calories are then stored in other organs such as the heart, skeletal muscles, liver or pancreas, which can lead to impaired organ function. This is associated with insulin resistance and impairments in fat and sugar metabolism, and can result in liver disease, type 2 diabetes and cardiovascular disease. There are variations in fat cell size and number between individuals, and this can affect cardiometabolic health. For example, someone with obesity may have more smaller, healthier fat cells, while another person with the same BMI may have fewer but larger, unhealthier fat cells. This may explain why one individual with obesity is more likely to develop chronic diseases than another.’ ****
Goossens explains that adipose tissue is an endocrine organ that not only stores and releases lipids, but also produces a variety of signalling molecules that affect our metabolism. Leptin, discovered in the 1990s, is one such important signalling molecule produced by adipose tissue, acting as a satiety hormone in the brain. The discovery of leptin was a scientific milestone and dramatically changed our view of adipose tissue. When something goes wrong within the adipose tissue, serious health problems can arise. The progress in research into the role of adipose tissue in obesity is impressive. ‘We have developed techniques to investigate adipose tissue and metabolism in living humans, but we are not there yet,’ he adds. Understanding the role of adipose tissue is crucial for developing strategies to prevent and treat health problems and relieve pressure on the healthcare system.
Differences between abdominal fat and lower body fat
Adipose tissue is not uniformly distributed in our body. Fat can be stored under the skin as subcutaneous fat, in the abdominal cavity as visceral fat and can also accumulate within and around organs. One of Goossens points of focus is to better understand the differences between fat stored in the upper body (abdominal fat) and fat stored in the lower body. ‘For example, there are clear differences between men and women in body fat distribution. Females store fat more often in their lower body, while males store fat more often in the abdominal region. Research has shown that abdominal fat is much more detrimental to overall health than fat storage in the lower body; this is partly due to differences in fat metabolism and the production of inflammatory factors between these fat depots.’ *** Recent research shows that in the lower body, fat cells may still be able to increase in number with weight gain, while in abdominal fat, existing fat cells become much larger and therefore function less well.
‘We recently presented a new framework for the diagnosis, staging and treatment of obesity*, proposing to look at waist circumference in relation to height, among other factors,’ Goossens said. ‘Differences in body fat distribution and the functioning of this organ may partly explain why the effectiveness of interventions such as lifestyle changes or medication may vary between males and females.’
Impact of obesity research and the future
More health gains through a tailored approach
An important and trending topic in the scientific field is identifying subgroups within populations, and investigating the characteristics that make a particular group of people respond better to certain interventions. Goossens: ‘An important goal of our research is to eventually be able to predict – based on a person's biological characteristics – which intervention will likely be most effective.’ One example is precision nutrition, a tailored nutritional approach. Research shows that the pathway to type 2 diabetes can be different between individuals. Some individuals develop more insulin resistance in skeletal muscles, others predominantly in the liver. ‘Recently, we have shown that by fine-tuning dietary patterns (within the guidelines healthy nutrition) to the metabolic phenotype of an individual, additional health gains can be achieved, ‘** says Goossens.
Goossens explains that the goal is to make simple measurements that can eventually be performed in practice, rather than in a research institute. ‘The ultimate goal is to be able to predict which intervention is most likely to succeed based on factors such as BMI, sex, age, fat distribution and some biomarkers in the blood.’ Developing an algorithm that can determine the best approach for an individual based on this data is not easy, as it is not yet known exactly which biomarkers are needed for this, but new technologies can help identify the right factors.
Chair of Cardiometabolic Physiology of Obesity
The focus of Goossens' new chair is on better understanding the overall health differences between people with obesity. He wants to investigate the causes behind these differences. ‘By better understanding underlying biological impairments, which may differ between individuals with obesity, we can develop more effective prevention and treatment strategies tailored to certain subgroups of the population.’ This is all about a tailored approach. ‘Further to that, when evaluating the effectiveness of obesity interventions, we really need to look beyond body weight. Instead, we need to focus on improvements in cardiometabolic health, quality of life and general well-being,’ says Goossens. New insights into the role that adipose tissue plays in this could lead to innovative treatments and a healthier future.
Stop the stigma
As an opponent of obesity stigma, Goossens feels that it is crucial to show empathy for people with overweight. He stresses that people with obesity often face judgement and prejudices, both from the general public and healthcare professionals. This makes the situation even more challenging for these individuals. Many people with obesity do their best to live healthy lives but are not always taken seriously, this is frustrating and demotivating. ‘We know that the stigma surrounding obesity can have several negative consequences, such as chronic stress and a decrease in self-confidence. People with obesity who experience this societal disfavour are also less likely to seek help. Stigmatisation of people with obesity is associated with a lot of hidden suffering and lower quality of life.’
To address this problem, Goossens advocates for more awareness among healthcare professionals and a more empathetic, but also more effective approach. He points to the Vitaliteitsloket (vitality desk) pilot at Maastricht UMC+, where patients are better guided and given the opportunity to discuss their problems as well as being given the chance to be referred to the right care provider. This approach can help reduce stigma and support people more effectively.
Conclusion
In his inaugural address on 11 October, Goossens directed some crucial messages to the general public: ‘Obesity is a complex chronic disease and not simply a consequence of an unhealthy lifestyle. The causes and consequences of obesity can differ between individuals. Therefore, the effects of certain interventions on health are not the same in everyone. Obesity is certainly not always a matter of ‘eigen schuld dikke bult’ (it serves them right). By looking beyond body weight and focusing on more tailored approaches, we can develop more effective interventions and reduce the impact of obesity on individuals' overall health. It is essential to show empathy for people with obesity and support them in their quest for a healthier life. By investing in research and raising awareness of the stigma surrounding obesity, we can prevent obesity or treat it better, creating a healthier future for all.’
‘By better understanding underlying biological disruptions, which may differ between individuals with obesity, we can develop more effective prevention and personalised treatment strategies’.
References
**** Goossens GH. The Metabolic Phenotype in Obesity: Fat Mass, Body Fat Distribution, and Adipose Tissue Function. Obes Facts 2017; 10: 207-215.
*** Goossens GH, Jocken JWE, Blaak EE. Sexual dimorphism in adipose tissue, skeletal muscle and liver metabolism - the impact on cardiometabolic health. Nat Rev Endocrinol 2021; 17: 47-66.
*Busetto L, Dicker D, Fruhbeck G, Halford JCG, Sbraccia P, Yumuk V, Goossens GH. A new framework for the diagnosis, staging and management of obesity in adults. Nat Med 2024; 13: 439–452.
** Trouwborst I, Gijbels A, Jardon KM, Siebelink E, Hul G, Wanders L, Erdos B, Péter S, Singh-Povel CM, de Vogel-van den Bosch J, Adriaens ME, Arts ICW, Thijssen DHJ, Feskens EJM, Goossens GH, Afman LA, Blaak EE. Precision nutrition by modulating dietary macronutrients according to tissue-specific insulin resistance phenotypes improves cardiometabolic health. Cell Metab 2023; 35: 71-83.
Text: Danielle Vogt
Photos: Appie Derks
Did you enjoy reading this article? Follow us on Instagram and LinkedIn for more exciting news!
Also read
-
During the 2023 ERS International Congress in Milan (Italy), the ERS presented the ERS Lifetime Achievement Award 2023 to Professor Martijn Spruit.
-
And how can it be counteracted? According to Luc van Loon, you can become a bodybuilder even after age 80. 'But the disadvantage of our dynamic muscles is that you also lose them quickly when you start using them less. Maintaining muscles is an active process. You have to keep stimulating them.' NUTRIM professor Luc van Loon in Volkskrant in “BETTER LIFE”