Palm oil is an edible vegetable oil derived from the mesocarp of the fruit of the oil palms. Like all fats, it is composed of fatty acids, esterified with glycerol. It has an especially high concentration of saturated fatty acids, specifically the 16-carbon saturated fatty acid, palmitic acid (PA), to which it gives its name. The highly saturated nature of palm oil renders it solid at room temperature in temperate regions, making it a cheap substitute for butter or hydrogenated vegetable oils in uses where solid fat is desirable, such as the making of pastry dough and baked goods. The health concerns related to trans fatty acids in hydrogenated vegetable oils may have contributed to the increasing use of palm oil in the food industry. Nevertheless, excessive intake of palmitic acid, which makes up 44% of palm oil, increases blood levels of low-density lipoprotein (LDL) and total cholesterol, and so increases the risk of cardiovascular diseases. Moreover, The European Food Safety Authority (EFSA) and the World Health Organization have already declared that glycidol (which is a compound formed by processing of palm oil) is genotoxic and carcinogenic.

In a recently published article by Nature, they reported experiments on mice fed with palmitic acid discovering that it promoted oral cancers and deadly skin melanomas. Indeed, cancer cells exposed to palmitic acid for a short period spread quickly - even once it was removed from the diet. The study in Nature showed this 'memory' is caused by epigenetic changes to how our genes function. They alter the function of metastatic cancer cells - allowing them to form a neural network around the tumor and spread more easily. Their findings not only underscore the long-term health risks associated with a diet rich in PA regarding metastatic progression but also provide mechanistic insights to identify new epigenetic- and neural/glial-related therapeutic strategies to attenuate and prevent distant dissemination.

Indeed, the team uncovered a way to block it: antibodies to stop metastasis in a range of cancers are being developed.

However, further studies are necessary to investigate palmitic acid exposure and metastasis interactions.