My name is Sixten Harborg, and I am a Physician and Clinical Research Fellow at the Department of Oncology, Aarhus University Hospital. I investigate the impact of obesity and metabolic health on cancer outcomes, with the goal of improving survivorship in patients with obesity who develop cancer.
My expertise lies at the intersection of oncology and metabolism, specifically looking at how obesity affects cancer risk and outcomes. I focus on improving care for patients with obesity who develop cancer – for example, studying how body composition and metabolic health influence cancer recurrence and survivorship, and finding ways to optimize treatment and follow-up for these patients. This involves both clinical work with cancer patients and research using large patient registries to uncover patterns and potential interventions that could help improve survival and quality of life for individuals with obesity facing cancer.
What does a typical workday look like for you?
I usually split my time between clinical duties and research. On a typical day, I start off at the hospital seeing patients – for instance, conducting morning ward rounds or outpatient clinic visits. After the clinical consultations, I transition into research mode. This might involve analysing data from our studies (I work a lot with large databases to study cancer risk and outcomes), writing or revising research papers, and hopping on meetings with collaborators to discuss ongoing projects. I also spend some time mentoring medical students and junior researchers, which I find very fulfilling. No two days are exactly the same, but balancing patient care with research keeps things exciting. It is busy, for sure, but I enjoy the variety and that sense of dual contribution is what I thrive on.
What first sparked your interest in working in the field of obesity?
During my medical and research training, I realized that improving cancer outcomes is not only about treating the tumor, but about long-term survivorship. Metabolic health and obesity are often overlooked in cancer care, despite their clear relevance for treatment tolerance, recurrence, and quality of life, and that realization shaped my research focus.
What’s one tool, method, or hack that makes your work life easier that you wish everyone knew about?
One tool that has been a real game-changer for me is a good and easy-to-use reference manager. I use Zotero to organize literature, which saves an enormous amount of time when writing papers or revisiting studies months later. For day-to-day productivity, I rely on the Pomodoro technique to structure focused work sessions, especially for writing and data analysis. I also use Trello to manage research projects, track manuscripts, analyses, and deadlines across multiple collaborations. Finally, a good pair of noise-cancelling headphones has become essential for maintaining concentration in busy clinical and academic environments. Together, these tools help me stay organized, focused, and efficient.
How has being part of the ECN changed your journey so far?
Being part of the EASO ECN became truly tangible for me after attending the ECN Winter School in Turkey in 2023. It gave me direct access to peers and senior researchers working on closely related questions, and those connections have translated into ongoing collaborations, continued scientific exchange and invitations for lectures and presentations abroad. Beyond the formal program, the ECN has functioned as a community where it is easy to reach out, sense-check ideas, and connect across borders and disciplines. This is something that has been especially valuable when working with obesity and cancer, which is a very under investigated area.
What has been the most rewarding or exciting project that you’ve worked on?
The most rewarding and exciting experience has been my time as visiting researcher at Harvard, where I had the opportunity to work closely with leading researchers in obesity, metabolism, and cancer epidemiology. Being immersed in that environment strengthened my methodological skills, expanded my international collaborations, and, importantly, shifted how I think about obesity research. From describing associations to understanding etiologic and translational mechanisms. The project and the learnings from it reinforced the importance of metabolic health in cancer survivorship and has had a lasting influence on both my current projects and future research direction.
What’s one piece of advice you’d give to the “you” who was just starting out?
I would tell my younger self to embrace collaboration and mentorship early on. Do not be shy about reaching out to senior researchers or peers in other departments or countries. Science is a team effort.
What excites you most about the future of obesity research?
What excites me most is the increasingly interdisciplinary approach the field is taking. We have experts in endocrinology, public health, genetics, psychology and even fields like oncology (were I come in) all coming together. I am also enthusiastic about the wave of new therapies and tools on the horizon. We are seeing medications for weight management improving even more as well as digital health tools that could personalize lifestyle interventions for individuals. I believe the idea of precision medicine in obesity, where we can tailor our treatments to e.g. an individual’s specific metabolic profile or genetic background is becoming more realistic, and that is very exciting. Another aspect I observe among healthcare colleagues is the growing awareness and destigmatization of obesity. The more societies and healthcare systems recognize obesity as a complex chronic condition, the more support and funding go into research and into comprehensive care for patients. I believe the field is moving fast and in a positive direction and in the near future I think we will also see obesity integrated more into other clinical specialties as a part of a more holistic care plan for e.g. cancer survivors.
Where do you see yourself in five years – what’s your dream project or role?
I aim to be a physician-scientist working across a university and university hospital, focused on reducing obesity-related cancer burden and improving survival for patients with obesity and cancer.
What kinds of projects or initiatives would you be most interested in collaborating on with other ECN members?
I am very open when it comes to collaboration, some of the best projects I have been a part of started from simple conversations with colleagues. Within the ECN, I am particularly interested in collaborative projects that bring together different perspective on obesity across disciplines and countries.
I warmly invite anyone working on cancer risk related to obesity, obesity-related metabolic conditions, or cancer survivorship among individuals with obesity to reach out. I am especially enthusiastic about collaborations that connect biological or translational insights with large-scale population data and translating findings from the lab into clinically meaningful research using the large cohorts I have access to. I see real potential in combining complementary expertise to better understand mechanisms and ultimately improve outcomes for patients.
Connect with Sixten!
Email: sixten.harborg@oncology.au.dk
LinkedIn: https://www.linkedin.com/in/sixten-harborg-md-760867152/
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