Peat Archive

Ray Peat's position on polyunsaturated fatty acids (PUFAs) is perhaps his most well-known and controversial stance. He argued that the so-called 'essential fatty acids' — linoleic acid (omega-6) and linolenic acid (omega-3) — are not truly essential and are in fact among the most harmful substances in the modern diet. He traced the promotion of vegetable oils to the paint and chemical industries seeking new markets for their products.

Peat documented extensive evidence that PUFAs suppress thyroid function, promote lipid peroxidation, interfere with proteolytic enzymes, suppress the immune system, and promote cancer. He noted that these fats accumulate in tissues over years and are extremely difficult to eliminate. He recommended avoiding vegetable oils, nuts, seeds, and fish oil, and instead using coconut oil, butter, and other saturated fats for cooking.