This kind of smells of bad science reporting, the paper itself does not seem to be bad science, but I haven't read the paper yet (DOI 10.1038/s41586-021-04075-0

This kind of smells of bad science reporting, the paper itself does not seem to be bad science, but I haven't read the paper yet (DOI 10.1038/s41586-021-04075-0); a quote from the abstract basically, indicates they were force-fed unrealistically high palmitic acid content combined with the standard lab mouse fake feed diet. It also indicates the palmitic acid did not cause the cancer, but only increased its growth. "Here we show that dietary palmitic acid (PA), but not oleic acid or linoleic acid, promotes metastasis in oral carcinomas and melanoma in mice. Tumours from mice that were fed a short-term palm-oil-rich diet (PA), or tumour cells that were briefly exposed to PA in vitro, remained highly metastatic even after being serially transplanted (without further exposure to high levels of PA)." Mammals produce palmitic acid as the primary fatty acid during de novo lipogenesis (humans are estimated to have about 1/3rd of their body fat stored as palmitic, possibly more in strict vegetarians than everyone else), and palmitic acid is required for building the membranes of cells and subcellular structures (palmitoylation, a process that is used in the production of several thousand chemicals in the body). Fundamentally, if they would have not had this outcome, then it would indicate we don't understand something fundamental about biochemistry. If you put fuel on a fire, the fire will grow. If you feed a cancer the ingredients it requires, then it will grow. Cancer does not really do anything special that any other cell doesn't already do (the form of "high copper" anaerobic metabolism it uses not withstanding); palmitic acids, and saturated fatty acids in general, are required for cellular growth, hormone construction, energy production, and an otherwise endless list of functions required for life. The paper isn't saying "don't eat palmitic acid rich diets", which the science news seems to be trying to imply the paper says, and if it had said so, would be bad science in of itself; what it's saying is we should look into short term low palmitic acid diets as an adjunct therapy for cancer treatment. That said, if you're looking into keeping cancer from starting in the first place, the semi-traditional human diet of one meal a day, sometimes with intermittent fasting thrown on top, seems to make sure cancer is kept at bay with our normal apoptosis cycle; apoptosis in humans only can re-engage after the postprandial insulin spike after 12 to 24 hours, depending on the individual. Saturated fats, including palmitic acid, are required to keep an individual functioning without being hungry all day long, but also to replace damaged cells garbage collected by apoptosis and also drive apoptosis itself.