Palm oil study raises major concerns over role in metastatic cancer

Palm oil is controversial due to its role in deforestation, but the oil is also the subject of a number of studies that raise potential health concerns. The latest among those studies is new research from IRB Barcelona, where scientists found a concerning link between palm oil and cancer metastasis, at least when it comes to tumor cells transplanted into lab mice.

The study specifically focuses on palmitic acid, a saturated long-chain fatty acid found in palm oil. For its part, palm oil is a type of vegetable oil that is used in a variety of products, including cosmetics and some foods. Though the oil is high in antioxidants, some studies have raised possible health concerns, particularly when the oil is oxidized by heating and then reheating.

The new study from IRB Barcelona looked into palm oil's potential impact on cancer, particularly the spread of a cancerous tumor to other parts of the body. This change in cancer status, which is known as metastasis, makes the disease much harder to treat and often leads to death.

A diet high in palmitic acid may make primary cancer tumor cells more "aggressive," the study found, increasing the risk of metastasis. That's based on the results of transplanting tumor cells from melanoma and oral cancer into mice. The cells were harvested from patients who had high levels of palmitic acid in their diet.

Even a short-term diet rich in palmitic acid was found to increase the cells' capacity for metastasizing to other parts of the body from the primary site. The researchers say the palm oil fatty acid triggers a permanent epigenetic change in the cells called "stable memory" that gives them more aggressive capabilities.

Though the researchers had previously observed a link between metastasis risk and palmitic acid, this new study sheds light on how the fatty acid may contribute to this problem. Epigenetics are identified as the potential driving factor behind this observation, as similar links weren't made between olive oil's oleic acid or flaxseed oil's linoleic acid.

By identifying the mechanisms behind this change, the researchers say it may help with the development of a way to reverse the aggressiveness and block cancer metastasis.