For example in mice, excess of long-chain polyunsaturated fatty acids (PUFA) in a western diet instigates metabolic enteritis that is restricted by the antioxidative enzyme GPX4 (glutathione peroxidase 4) [5,6], and excess of sugar or food colorants promotes experimental colitis by perturbation of the intestinal microbiota [7,8]. Here, GPX4 is linked to colitis.