Inside the Science of Diet & Cancer Prevention

As research continues to reinforce the connections between nutrition, metabolism, and disease, diet emerges as a promising tool in cancer prevention and treatment. Dr. Gerardo Mackenzie, Professor and Chair of the UC Davis Department of Nutrition, is leading innovative research that explores how dietary factors influence cancer development, progression, and response to therapy; particularly with pancreatic cancer. By studying the interactions among diet, metabolism, and the immune system, this work aims to better understand how nutrition can support more effective cancer treatments.

The Power of Omega-3 Fatty Acids

A major focus of Dr. Mackenzie’s lab is understanding how excess adiposity contributes to pancreatic cancer and identifying nutritional strategies that may help reduce cancer risk.mega-3 fatty acids are widely recognized for their anti-inflammatory effects. By studying omega-3s in the context of obesity and cancer development, Dr. Mackenzie’s research team has discovered insights that emphasize not only what we eat, but also the importance of timing for dietary interventions.

“One of the most surprising findings from our research was that omega-3 fatty acids were able to reduce pancreatic carcinogenesis before obesity was established.” However, he added that this protective effect disappeared once obesity had already developed, emphasizing that “timing matters when it comes to dietary intervention.”

Together, these results suggest that omega-3 fatty acids may be most impactful as a preventive strategy, rather than as a means of helping to lower cancer risk after obesity is present. This work highlights the importance of early, sustained nutrition habits and reinforces the idea that long-term dietary patterns can significantly influence disease risk.

Beyond omega-3 fatty acids, Dr. Mackenzie’s lab is also examining how diet shapes the gut microbiome and how these changes may influence responses to immunotherapy. By altering the microbiome through both dietary approaches and targeted drugs, this research aims to better understand how nutrition can support immune-based cancer treatments and improve therapeutic outcomes.

The Ketogenic Diet in Relation to Cancer

In addition to studying individual nutrients, Dr. Mackenzie’s research also explores broader dietary patterns and how they may influence cancer treatment. One area of growing interest is the ketogenic diet, which is a high-fat, very low-carbohydrate diet that has been used clinically for decades to manage certain specialized conditions. More recently, it has gained attention in cancer research because of its possible effects on metabolism.

Dr. Mackenzie explained that this interest is rooted in how cancer cells generate energy. “Cancer is a metabolic disease,” he said, noting that many cancer cells rely heavily on glucose through a process known as aerobic glycolysis. By sharply reducing carbohydrate intake, a ketogenic diet may limit glucose availability to cancer cells. Ketone bodies may also directly influence cellular metabolism. Potential benefits include reduced glucose availability, altered insulin signaling, and possible anti-cancer effects of ketone bodies themselves.

At the same time, Dr. Mackenzie emphasized that a traditional ketogenic diet may not be appropriate for all patients, particularly those undergoing cancer treatment. The high-fat intake required can also be difficult to adopt and maintain. Because of this, his lab is exploring alternative approaches, including intermittent ketogenic diets and ketone esters, which may help achieve metabolic benefits without requiring sustained, extremely high-fat consumption.

Diet and the Future of Cancer Care

Looking ahead, Dr. Mackenzie believes nutrition will play a massive role in the future of cancer care. As understanding of cancer biology improves, treatments are becoming more personalized, and diet may be tailored to specific tumors, genetic variants, and patient needs. Diet has the potential to reduce side effects of chemotherapy, improve treatment response, and support overall quality of life. Because diet also influences the gut microbiome, which can affect cancer treatment outcomes, nutrition is likely to become an increasingly important part of personalized cancer therapy. Dr. Mackenzie’s research highlights a clear message. “Diet is not just supportive care–it is an essential component of cancer prevention and treatment.”