Why are seed oils bad for you and what is the order of worst to best

The debate around seed oils centers on their health impacts, particularly due to their high calorie content and the fact that they are sources of polyunsaturated fats like omega-6. Layne Norton points out that seed oils have become a significant part of the increased calorie intake in modern diets, which can contribute to health issues. However, when polyunsaturated fats from seed oils replace saturated fats in the diet, studies often show either neutral or positive health outcomes in terms of inflammation and cardiovascular health 1.

He also highlights that strong evidence against seed oils is lacking. Claims about their negative health impacts often rely on animal studies, in vitro mechanisms, and epidemiological data, which aren't considered high-quality evidence on their own 2. The complexity is further increased by the variability among individual fatty acids within each category, whether saturated or unsaturated 3.

As for ordering oils from worst to best, Norton stresses that replacing saturated fats with polyunsaturated and monounsaturated fats is generally more beneficial for metabolic health and cardiovascular disease risk. Thus, oils higher in these fats, like olive oil, are generally favored over those high in saturated fats 3 4.