On 22 December 2015, the United Nations General Assembly established the International Day of Women and Girls in Science. Celebrated annually on 11 February, this day recognises the vital role women and girls play in science and technology.

The International Day is for promoting full and equal access to, and participation in, science, which is essential. Increasing the number of women in science not only drives innovation but also enriches research with diverse perspectives, fostering creativity and new approaches to problem-solving.

To mark this occasion, we spoke with former EASD President Professor Juleen Zierath, an internationally renowned scientist, about her journey in science, the challenges she has faced, and her advice for aspiring women in science.

1. What inspired you to pursue a career in science, and how did your journey unfold?

From a young age, I was always interested in sports and athletics, which naturally led to a fascination with the human body – its physiology, kinesiology, and biomechanics. I became fascinated by how science could help us understand movement and performance. As I got older, I realized there was still so much we didn't know about the body, and I wanted to explore those unknowns.

A pivotal moment came when I was about 9 years old. My grandfather underwent bypass surgery, which was a frightening experience as I was very close to him. One of the recommendations that the doctors gave him after the surgery was to change his diet and exercise patterns, which my grandfather did, and he went on to live until he was 95! This experience left a lasting impression on me, demonstrating the power of exercise and diet as a medicine to improve overall health.

Today, I serve as the Executive Director of the Novo Nordisk Foundation Center for Basic Metabolic Research at the University of Copenhagen, which comprises about several teams conducting basic research on cardiometabolic disease. In addition to this role, I lead my own research team studying how exercise influences metabolism and its potential to combat diseases like diabetes and obesity.

Additionally, at the Karolinska Institutet in Stockholm, my research is centred on translational studies aimed at identifying and validating key targets in metabolic disease, with a particular focus on glucose and energy homeostasis, as well as overall muscle strength. Beyond research, my role at both institutions also involves mentoring and developing young scientists, helping them find their own paths in this exciting field of metabolic research.

2. What challenges have you faced as a woman in science, and how did you overcome them?

One of the biggest challenges I faced was navigating a career in science without having many role models. I was a first-generation college student and didn’t know many women who had gone to university, let alone pursued careers in research. A turning point for me was meeting my advisor during my undergraduate studies. She was the first female professor I had ever encountered, and seeing her inspired me to pursue my Master’s degree, where I focused on exercise metabolism and bone health.

Later, I had the incredible opportunity to work with John Holloszy at Washington University School of Medicine, which was really inspiring. Through that experience I learned about the rich history of Scandinavian research in muscle physiology and exercise.

I had never travelled outside the U.S. before, but when the opportunity arose to continue my research at the Karolinska Institutet in Stockholm, I took a leap of faith – I bought a one-way ticket, packed everything I owned into three suitcases, and moved to Sweden. At times, I questioned my decision – I had no social network, no family or friends, and had left behind everything familiar. But once I arrived, I found an incredibly collaborative research environment, where clinicians and basic scientists worked together to bridge the gap between lab discoveries and clinical applications.

3. What advice would you give to young women aspiring to pursue a career in science?

First and foremost, follow what you’re truly passionate about. Science is full of highs and lows, and your passion will be what sustains you through the difficult moments.

Second, get solid fundamental training in strong research environments where you’ll be exposed to diverse perspectives. Being in a setting where your ideas are challenged and where you learn to defend them with evidence is crucial for your development as a scientist.

Persistence is also key – this is a tough field, and setbacks are inevitable. Funding is competitive, experiments don’t always go as planned, and progress can be slow. But patience and resilience are essential, especially when working in fields like biomedical research, where translating discoveries from the lab to clinical practice takes time.

Finally, build a strong support network. Surround yourself with mentors, peers, and collaborators who will challenge, support, and inspire you throughout your career. Science is a team effort, and having a community that encourages and pushes you forward makes all the difference.

As we celebrate the 2025 International Day of Women and Girls in Science, Professor Juleen Zierath’s insights serve as a powerful reminder of the importance of diversity and inclusion in research. Her experiences highlight the value of perseverance, mentorship, and collaboration in driving scientific progress.