Fat in common cooking oils linked to aggressive breast cancer, finds study

A new study from Weill Cornell Medicine in New York, United States, has found that linoleic acid, a type of omega-6 fat found in seed oils like soybean and safflower oil, as well as in animal products may accelerate the growth of triple-negative breast cancer, one of the most difficult forms of breast cancer to treat.

Published in Science on March 14, the study reveals that linoleic acid activates a tumour growth pathway in triple-negative breast cancer cells by attaching to a protein called FABP5, which is found in higher amounts in this cancer subtype. This effect was not seen in other breast cancer types.

In mouse experiments, a diet high in linoleic acid was shown to increase tumour growth in triple-negative breast cancer. This connection could be the first clear explanation for how certain dietary fats might influence cancer development.

Triple-negative breast cancer is particularly challenging to treat because it lacks the three main hormone receptors (estrogen, progesterone, and HER2) that other breast cancers rely on making it unresponsive to many existing treatments.

The study suggests that FABP5 could serve as a biomarker, helping doctors identify which patients may benefit from specific diets or targeted treatments. It also opens the door to using dietary strategies as part of cancer care for this subtype.

While linoleic acid is essential for health, its levels in modern Western diets have surged since the 1950s due to the popularity of processed and fried foods, leading to concerns about its impact on chronic diseases.

Interestingly, researchers also found hints that this same linoleic acid FABP5 pathway might play a role in prostate cancer, obesity, and diabetes, suggesting the impact could be broader than just breast cancer.