A study conducted by scientists from Harvard University and Princeton University has revealed that animal fats accelerate the growth of cancerous tumors, whereas plant-based oils such as olive oil, coconut oil, and palm oil have a protective effect on the immune system.
Groundbreaking research published in Nature Metabolism, a scientific journal focusing on metabolism and related fields, showed that our choice of cooking oils may have a far greater impact on health than previously thought. The study, led by researchers from world-renowned institutions such as Harvard and Princeton, demonstrated that animal fats like butter accelerate tumor growth, while plant-based oils such as palm, coconut, and olive oil help preserve immune system function.
The research was carried out on mice that were fed diets with identical calorie levels but different fat sources. Findings revealed that tumors developed more rapidly in obese mice fed with butter, while this adverse effect was not observed in mice consuming plant-based oils despite having the same body weight. The researchers confirmed that the key reason behind this difference lies in how fats affect the immune system. Animal fats were found to impair the function of the body’s cancer-fighting defense cells, while plant-based oils protected them.
Despite these findings, butter—which holds an indispensable place in Turkish cuisine for its flavor and tradition—does not need to be completely abandoned. Researchers recommend a “balanced approach” rather than a radical change. For example, small amounts of butter may be used to enhance flavor, while palm or other plant-based oils are suggested as the main cooking fats. This approach underscores that the type of fat, rather than the quantity, is of greater importance.
The study was funded by respected nonprofit organizations such as The Mark Foundation and the U.S. National Institutes of Health (NIH), reinforcing its scientific credibility and independence. Led by Prof. Lydia Lynch, the international research team included participation from institutions such as Trinity College Dublin, Brigham and Women’s Hospital, and Harvard Medical School. The findings once again highlight the importance of focusing on the quality of dietary habits in both the fight against obesity and cancer prevention.
Scientists emphasize, however, that since the study was conducted on mice, further research is needed before the results can be confirmed for humans.
