New Australian research has found that popular fitness and supplement videos on TikTok can leave young men feeling worse about their fitness and nutrition, and increase their interest in using muscle‑building supplements. The Flinders University study, published in the international journal Body Image, is one of the first to experimentally test the immediate impact of TikTok content on young men’s body satisfaction and health intentions

Hormones influence almost every process in the body, but public understanding of their role in health and wellbeing is limited. Today, Friday 24 April 2026, the global endocrine community joins forces to mark World Hormone Day and improve awareness of what hormones are, why they matter and the small steps we can all take to promote good hormone health. 

This initiative, led by the European Society of Endocrinology (ESE) with a group of over 120 organisations including national and country endocrine societies, specialist societies, patient advocacy groups and other groups active in the field, has many activities taking place around the world today, online and in person, under the banner of #BecauseHormonesMatter. World Hormone Day 2026 builds on the momentum of last year’s campaign, which reached an estimated audience of more than 136 million people, with activities in 40 countries and 25 languages. 

With so much information about hormones available online, World Hormone Day is an opportunity to share clear and credible information with the public. 

Prof Wiebke Arlt, ESE President, said: “Hormones affect almost every aspect of our health, yet many people only think about them when something goes wrong. They might look online for help and feel confused by what they find or uncertain about what to trust. World Hormone Day is an opportunity to improve understanding and, importantly, to share practical, evidence-based steps people can take to support their hormone health throughout life.” 

ESE and the wider endocrine community encourage individuals, patient groups, healthcare professionals and organisations worldwide to take part, share activities and help raise the profile of hormone health.

This year’s campaign is supported by a range of new and updated materials, including social media materials, infographics, posters, videos and how-to guides, designed to support engagement at local, national and international level. The materials are available for anyone to download, adapt and use in their own community.

Join in the conversation online using #BecauseHormonesMatter.