Published: 4.6.2026
Text: Francisco Acosta
Editing: Viestintätoimisto Jokiranta Oy
Image: Shutterstock

In Finland, approximately 60 percent of adults are overweight or obese according to the WHO, while the Finnish Diabetes Association estimates that one in ten Finnish individuals is affected by diabetes. These trends underscore the urgent need for innovative therapeutic strategies that not only promote remission of obesity and type 2 diabetes but enable their prevention before metabolic dysfunction develops.

Increasingly diversified therapeutic approaches

Lifestyle modification, including diet and physical activity, has long been the cornerstone of obesity and cardiometabolic disease management. However, large studies show limited long-term efficacy, as many individuals experience weight regain or relapse after initial success.

As a result, pharmacotherapy and metabolic and bariatric surgery have become key treatment options. Companies, such as Novo Nordisk and Eli Lilly and Company, have developed effective anti-obesity medications, including semaglutide, which produce substantial weight loss but require ongoing use. For the time being, bariatric surgery remains the most effective long-term intervention, but it is invasive, carries some surgical risks and is less scalable.

The main effects of these approaches rely on appetite suppression, while approaches that increase energy expenditure remain underexplored and represent an important area for future research.

Brown fat spends calories

Brown fat tissue (BAT) is a specialized thermogenic fat depot, with a unique capacity to dissipate energy as heat, thus helping to spend more calories, while simultaneously burning glucose and lipids. Although brown fat represents only a small fraction of total body mass, growing evidence suggests that it may exert meaningful systemic metabolic effects, especially through its endocrine function.

Notably, recent studies have shown that individuals with detectable brown fat exhibit a lower risk of type 2 diabetes, dyslipidaemia, hypertension, and cardiovascular diseases, compared with those in whom BAT is absent. These findings have positioned brown fat activation as an attractive therapeutic strategy for improving systemic metabolic health.

More research is required

To date, most approaches aimed at enhancing brown fat metabolism – such as nutritional or pharmacological strategies – have shown limited efficacy or have been associated with unwanted off-target effects. Regular cold exposure remains the only intervention that has consistently been shown to enhance brown fat activity without major adverse effects, with associated improvements in insulin sensitivity and/or glucose tolerance. However, its broader application is limited by poor tolerability, as cold exposure is often perceived as uncomfortable.

The limitations related to current therapeutic approaches highlight the need for a deeper mechanistic understanding of human brown fat biology to facilitate the development of more effective therapeutic strategies. In particular, there is a critical need to elucidate the cellular and molecular mechanisms that regulate brown fat activity and to determine how these pathways differ between individuals with metabolically active versus inactive brown fat. 

Brown fat activation as a new therapeutic approach?

To elucidate the biological processes regulating brown fat and its activation, our research group (Human Brown Fat Research Group Turku) is employing spatial transcriptomics together with complementary in vitro and in vivo approaches.

Our aim is to compare patients with metabolically active versus non-active brown fat tissue. We will, for the first time, comprehensively characterise the cellular composition, spatial organisation, intercellular interactions and key metabolic pathways of brown fat.

This integrated strategy will enable the generation of a detailed human brown fat atlas, serving as a critical resource for identifying cell populations and candidate genes associated with enhanced metabolic capacity. 

 

Francisco M. Acosta, PhD in Biomedicine, is an Academy Research Fellow (Adjunct Professor) at the Turku PET Centre, affiliated with the University of Turku and Turku University Hospital, and a member of the InFLAMES Research Flagship. His research is dedicated to unlocking the therapeutic potential of brown fat to combat metabolic disease. Dr. Acosta investigates strategies to enhance brown fat metabolism and studies the cellular and molecular mechanisms regulating brown fat activation in healthy individuals and patients with metabolic dysfunction. In addition, he explores the dynamic interplay between the immune system and brown fat to identify novel therapeutic avenues for obesity and metabolic disease.

More information: hbat.utu.fi