Andreas Stahl is the Ruth Okey Professor in the Department of Nutritional Science & Toxicology at UC Berkeley. His research focuses on developing innovative strategies to combat obesity-related disorders, including Type 2 diabetes and metabolic liver diseases. Stahl’s lab explores lipid metabolism, mitochondrial function, and adipose tissue biology, with a particular interest in engineering solutions for metabolic health.
QB3-Berkeley: Are there any emerging trends or technologies in your field that you’re excited about?
Andreas Stahl: One exciting development is the use of human-induced pluripotent stem cells (iPSCs) with microphysiological systems, also known as organs-on-a-chip. These technologies are becoming powerful tools for studying human metabolic disorders, an area where they haven’t been widely applied before.
A major focus is on obesity-associated diseases like type 2 diabetes and fatty liver disease, which have traditionally been studied using animal models, particularly rodents. While mice are genetically tractable, their metabolism differs significantly from humans. By integrating organ-on-a-chip systems with human stem cells, we can create more relevant models.
iPSCs closely reflect human biology and genetic diversity while allowing precise genotype modifications, something impossible with mice. Combining them with microphysiological systems enables physiologically relevant tissue volumes and media conditions while interconnecting different tissues to study crosstalk. These approaches are opening new possibilities for preclinical models of metabolic disease.
QB3: How do you see your research impacting society or the world in the next five to ten years?
AS: Our lab’s goal is to improve human health, with a focus on obesity-related disorders like diabetes and fatty liver disease. Over the past two and a half decades, we’ve explored mechanisms of lipid uptake, the role of ubiquinone (CoQ) in mitochondrial function, liver disease, and adipocyte biology.
Recently, we’ve integrated classical cell biology with bioengineering-inspired technologies. This includes studying biomechanical forces in brown adipose tissue, developing lipid nanoparticles to target adipose tissue and convert white fat into brown fat, and creating organ-on-a-chip models for metabolic research.
One of our latest projects is developing a fat-liver axis chip to replicate fatty liver disease progression and evaluate drug effectiveness. We hope these new tools and insights—shared with the scientific community—will advance drug discovery and preclinical testing in the near future.
QB3: What is brown fat and why scientists are so interested in it?
AS: Adipose tissue, commonly called fat, comes in different forms. White fat, which stores energy, varies depending on its location—subcutaneous fat in areas like the arms and thighs is less harmful than intra-abdominal fat, which surrounds organs and poses greater health risks.
Brown fat is fundamentally different. Rich in mitochondria, which contain iron and give it a brown color, its primary function is to generate heat rather than store energy. Humans maintain a body temperature of about 37°C, and brown fat plays a key role in non-shivering thermogenesis, burning large amounts of calories from lipids and carbohydrates to produce heat.
This makes brown fat an exciting target for obesity research. Since obesity-related diseases improve with weight loss, expanding brown fat activity could help burn excess calories, act as an “exercise mimetic,” and improve metabolic parameters like glucose and fatty acid levels.
QB3: How do you mentor young scientists interested in your field?
AS: Our lab fosters a highly collaborative culture, both internally and with partners across campus. Everyone contributes to the lab’s overall functioning, and while each researcher has an independent project, we encourage collaboration through shared technologies and approaches.
Beyond research, we prioritize community-building. We organize multiple lab outings each year, including dinners and brewery visits. A favorite tradition is our annual holiday white elephant gift exchange. Recently, we’ve also started weekend lab hikes, including a trip to Point Reyes, which I hope becomes a new tradition.
QB3: What inspires you and your work?
AS: The biggest inspiration comes from the excitement of discovery. Few things are more rewarding than forming a bold hypothesis and seeing it hold true—or discovering something unexpected. That thrill of exploration continues to drive me.
I’m also inspired by the academic freedom and collaborative environment at Berkeley. The brilliance of my colleagues and their willingness to share ideas creates an incredible research atmosphere. I don’t think we could achieve what we do without such a supportive and innovative community. It’s a privilege to be part of it, and it continually motivates me to uphold that high standard.