SAMA HOOLE: The cow took potentially problematic fats and fixed them for you. At no charge. Without being asked. Just doing its biology.

Here's something that should fundamentally change how you think about beef.

Cows eat grain. Grain contains polyunsaturated fats - the same unstable, oxidation-prone fats that cause problems in seed oils. Linoleic acid. Alpha-linolenic acid. The stuff that integrates into your… pic.twitter.com/gzvawLm7mE

— Sama Hoole (@SamaHoole) February 17, 2026

Here's something that should fundamentally change how you think about beef. Cows eat grain. Grain contains polyunsaturated fats - the same unstable, oxidation-prone fats that cause problems in seed oils. Linoleic acid. Alpha-linolenic acid. The stuff that integrates into your cell membranes and creates inflammatory signalling. But between the cow eating the grain and you eating the cow, something remarkable happens. Inside the rumen - the cow's first stomach, roughly the size of a dustbin - live billions of bacteria whose job includes biohydrogenation. They take those unstable polyunsaturated fatty acids and systematically convert them into stable saturated fats and conjugated linoleic acid (CLA). The biochemistry is elegant: the rumen bacteria strip hydrogen atoms and rearrange molecular bonds. Linoleic acid becomes stearic acid. Alpha-linolenic acid becomes palmitic acid. Unstable molecules become stable ones. Inflammatory precursors become neutral or beneficial fats. By the time that fat reaches the beef you buy, roughly 70-80% of the original polyunsaturated fat from the grain has been converted into stable saturated fat. The cow has done the work of an industrial refinery, except silently, continuously, and without chemical solvents. This is why beef fat is so resistant to oxidation. You can leave tallow on a shelf at room temperature for months without significant rancidity. The saturated molecular structure means it doesn't react with oxygen. It's chemically inert, stable, perfect for cooking, and for lining up your cell membranes. Compare this to the polyunsaturated fats in chicken and pork, which haven't been through any biohydrogenation, and which either oxidise during cooking or eventually in your cell membranes. The cow took potentially problematic fats and fixed them for you. At no charge. Without being asked. Just doing its biology. And then we were told the output of this process - saturated fat from beef - was the dangerous one.