Coffee drinkers have less fat, more muscle, and surprising hormone differences

Finland's researchers have discovered intriguing links between coffee consumption and health metrics in a new study. The study, published in the European Journal of Nutrition, analyzed data from 2,264 men and women, aged 46, participating in the Northern Finland Birth Cohort 1966. It found that those who drank more coffee tended to have lower levels of body fat, both total and visceral, as well as higher skeletal muscle mass, regardless of their body mass index (BMI).

Moreover, regular coffee drinkers had healthier glucose-insulin profiles, higher testosterone levels, and increased sex hormone-binding globulin (SHBG) compared to those who drank less. However, the hormonal effects were more pronounced in men, with higher coffee intake associated with greater total and bioavailable testosterone, as well as lower free testosterone and free androgen index.

The study's lead author, Luca Verroest, a doctoral researcher at the University of Oulu, noted that these hormonal differences persisted even after accounting for BMI and lifestyle factors. While these findings suggest a possible hormonal explanation for coffee's association with better metabolic health, they cannot definitively establish a causal link.

The study's relevance is heightened by Finland's status as one of the world's top coffee-consuming nations, with an average annual consumption of about 11.8 kilograms (26 pounds) per person. However, further research, including animal studies and human intervention trials, is needed to determine if coffee itself produces these biological changes and to identify the specific compounds responsible.