There’s never a year when a wellness trend doesn’t go viral. This year has seen people doing dopamine menus, NAD+ transfusions, and 20g creatine doses. While crazes come and go, making the sauna your core wellness tool is a practice that continues to go from strength to strength. Despite early records showing that people have enjoyed saunas for at least 7,000 years, new data on this practice continues to grow each year. We know the sauna makes us feel relaxed, healthier, and stronger from the inside out, but researchers are determined to learn more about the practical shifts it has on our bodies. To finish the year, we picked the most important insights of 2025 to show you why the sauna remains one of the simplest tools to improve how you feel, function, and age.