Fish Oil

Fish oil, rich in the highly unsaturated fatty acids EPA and DHA, is not an essential nutrient but a metabolic toxin whose apparent short-term benefits derive from its rapid oxidative breakdown. 3 Peat argued that the original 1929 experiments by the Burrs claiming essentiality for linoleic and linolenic acids were later disproven when the deficiency disease was cured by vitamin B6 rather than fats. 4 The long-chain omega-3 fats found in fish oil possess five and six double bonds, making them exponentially more unstable than seed oils. 3 This extreme instability means a large portion spontaneously oxidizes before even reaching the bloodstream, and it is these oxidative breakdown products that exert the celebrated anti-inflammatory effect by directly suppressing white blood cells and the immune response. 3

The anti-inflammatory action is fundamentally an immunosuppressive process analogous to the historical use of X-ray therapy for inflammatory diseases. 3 Peat noted that for the first few months, fish oil interferes with prostaglandin synthesis and inflammatory cytokines, providing symptomatic relief. 2 However, after approximately six months of continuous use, this effect transitions into a broader immune deficiency, increasing susceptibility to infections and, over a lifetime, contributing to cancer and degenerative conditions. 2 The oils' toxicity is not limited to immune cells; they exert antithyroid, antimitochondrial, and lipid peroxidative effects, directly suppressing mitochondrial respiration and glucose oxidation. 3

Chronically, the accumulation of these fats drives the aging process itself. Peat highlighted that the age pigment lipofuscin forms from the peroxidation of polyunsaturated fats, and fish oils are particularly potent inducers of this process in the brain, arteries, and liver. 2 In the brain, the concentration of these highly unsaturated fats correlates negatively with function; healthy newborns are metabolically "deficient" in them, while Alzheimer's patients exhibit markedly elevated levels of the oxidized neuroprostanes. 2 In the cardiovascular system, the fats form stabilized esters with cholesterol in atherosclerotic plaques, where their eventual oxidation contributes to arterial damage, contradicting the rationale that they prevent heart disease simply by lowering blood lipids through a toxic effect on the liver. 2

The commercial promotion of fish oil parallels earlier industry-driven campaigns for seed oils and radiation safety, with government agencies and journals selectively amplifying favorable research while ignoring contrary evidence. 2 Peat maintained that the only arguable benefit of omega-3 fats is that their extreme instability causes them to break down so rapidly that they are less easily stored as a chronic problem compared to the more stable omega-6 seed oils, and they can partially displace those seed oils in tissues. 8 In practice, he recommended strictly limiting all polyunsaturated fat intake, identifying olive oil, coconut oil, and butter as the safest dietary fats, with olive oil still warranting moderation due to its 10% PUFA content. 2