Natural Hormone FGF19 Reveals New Pathways for Fat Burning

A recent study has unveiled that the natural hormone FGF19 plays a crucial role in enhancing the body’s ability to burn fat and regulate energy expenditure. Conducted by researchers at the State University of Campinas in Brazil, the findings suggest that FGF19 may offer a new approach to treating obesity and related metabolic disorders. The research indicates that FGF19 activates specific brain functions that promote thermogenesis, enabling the body to utilize energy more efficiently.

Studies involving mice have demonstrated that FGF19, produced in the intestine, sends signals to the brain that influence energy usage. This hormone not only helps in burning stored fat but also improves weight management and stabilizes blood sugar levels in obese subjects. The mechanism was traced back to the hypothalamus, a vital brain region that integrates signals from the body and environment to manage energy metabolism.

Potential for Obesity and Diabetes Treatments

The implications of these findings are significant. Researchers believe that FGF19 could inspire the development of new medications aimed at combating obesity and diabetes. The strategy would involve creating compounds that mimic the body’s natural hormones, similar to the approach used in modern diabetes drugs like Ozempic, which contains semaglutide to increase feelings of fullness.

According to the study, FGF19 does more than just regulate appetite. It also reduces peripheral inflammation and enhances cold tolerance in the test subjects. Notably, when the sympathetic nervous system was blocked, the benefits of FGF19 were negated, indicating the hormone’s effectiveness is closely tied to this system. The research team observed that exposure to cold increased FGF19 receptor expression in the hypothalamus, suggesting an evolutionary role in how the body adapts to temperature changes.

Professor Helena Cristina de Lima Barbosa, from the Obesity and Comorbidities Research Center, stated, “FGF19 had already been linked to a reduction in food intake. Our work broke new ground by showing that it also plays an important role by acting on the hypothalamus and stimulating an increase in energy expenditure.”

Global Health Crisis and Urgent Targets

The findings come at a critical time, as the World Atlas of Obesity 2025 reports alarming trends in global obesity rates. The document warns that, without effective interventions, the number of individuals living with obesity could exceed 1.5 billion by 2030. Obesity is already responsible for approximately 1.6 million premature deaths annually from non-communicable diseases. In Brazil alone, around 31% of the population is classified as obese, with many adults failing to meet recommended physical activity levels.

FGF19, which is primarily produced in the small intestine, also plays a role in bile acid regulation and influences glucose and fat synthesis in the liver. While much research has focused on its functions in the liver, its effects on brain activity have been less explored.

Lucas Zangerolamo, a doctoral student and the first author of the study, emphasized the significance of their approach, which involved administering FGF19 directly into the brains of obese mice under controlled conditions. The results showed that central FGF19 signaling improved energy homeostasis by enhancing sympathetic nervous system activity and stimulating energy consumption in adipose tissue.

The research team is now focused on understanding which specific brain cells respond to FGF19. They have analyzed data from over 50,000 single cells in the hypothalamus to identify the populations that express FGF19 receptors. This future work aims to explore how to enhance the body’s natural production of this hormone and its connection to neural circuits that regulate eating behavior.

As the global health community grapples with rising obesity rates and associated health risks, the exploration of hormones like FGF19 offers promising avenues for innovative treatments and interventions. The study has been published in the American Journal of Physiology – Endocrinology and Metabolism, where it has been highlighted as a Top Article. The ongoing research will continue to investigate the complex interplay between FGF19 and the body’s metabolic pathways, potentially reshaping the landscape of obesity treatment.