Cancer is a genetic disease, but increasingly, researchers are beginning to view it as a metabolic disease as well. That’s because tumor growth isn’t simply the result of DNA mutations gone wild. It also involves changes in the structure and function of the mitochondria, the “powerhouse” part of our cells which are crucial for turning food into energy.
That’s why many experts are now emphasizing the importance of diet in preventing and treating various cancer types. In fact, according to the Mayo Clinic, 25% of all cancers could be prevented through dietary improvements alone.
What you eat is, of course, consequential. Research suggests that loading up on a wide variety of plant-based foods is a good place to start, since these provide ample fiber and phytochemicals such as antioxidants—both powerful anti-cancer nutrients.
However, a 2024 animal study published in Cell suggests that it’s not just what you eat that’s important, but also when you eat and how much. The researchers, a team at Memorial Sloan Kettering Cancer Center (MSKCC) in New York City, notes that intermittent fasting is “associated with improved outcomes in cancer.” They explain, “Our findings identify a link between dietary restriction and optimized innate immune responses, with the potential to enhance immunotherapy strategies.”
To understand the benefits of fasting in the prevention and treatment of cancer, the researchers restricted the diets of mice, denying them of food for two 24-hour periods per week. The animals were allowed to eat freely during the rest of the week, and as a result, they did not lose weight overall.
The team observed that the mice who engaged in periods of fasting experienced a “profound” change in their natural killer (NK) cells, white blood cells that destroy diseased cells, including those damaged by cancer. The study suggested that fasting helps these crucial white blood cells “survive in the harsh environment in and around tumors, while also improving their cancer-fighting ability.”
“Tumors are very hungry,” immunologist Joseph Sun, PhD, the study’s senior author, said via a news release. “They take up essential nutrients, creating a hostile environment often rich in lipids that are detrimental to most immune cells. What we show here is that fasting reprograms these natural killer cells to better survive in this suppressive environment.”
Adding to these benefits, the team also found that fasting caused the NK cells to travel into the animals’ bone marrow. There, the white blood cells are able to produce more Interferon-gamma, a protein that plays an important role in the immune system and anti-tumor response.
However, it’s important to emphasize that patients will have highly individualized needs: What works for one person could be dangerous for another. Malnutrition, fatigue, weight loss, and slow healing—all possible results of fasting—could complicate one’s care, especially if they are in active cancer treatment.
Speak with your doctor to find out if intermittent fasting is safe and advised before changing your diet.
For daily wellness updates, subscribe to The Healthy by Reader’s Digest newsletter and follow The Healthy on Facebook and Instagram. Keep reading: