Fish oil, as the name implies, is oil extracted from the tissues of oily fish—primarily mackerel, herring, and tuna. Cod liver oil, also as the name suggests, comes from the liver of cod fish. At first glance, they may seem harmless, even beneficial. But the truth is far darker: both are potentially dangerous for human consumption.

Even when cold-pressed or labeled “extra virgin,” these oils are extremely unstable. They oxidize rapidly—even within your stomach—producing destructive free radicals that your body struggles to neutralize. The widespread belief that omega-3 fatty acids are essential is a myth. The human body and brain do not require DHA or EPA from fish oil or cod liver oil. This misconception is not just false—it is dangerous.

The human digestive system is not forgiving. Certain parts, specifically within the duodenum, are so sensitive that touching them would feel like fire. Ayurveda calls this process “AGNI.” Fish oil, primarily derived from cold-water creatures, is too unstable to survive this fiery digestive process without harm.

Cod liver oil is often touted as a balanced source of vitamins A and D3. But this is misleading. Modern cod liver oil is not the same as the one your great-grandmother used. There are two forms of vitamin A: retinol and beta carotene. Beta carotene is a precursor, allowing the liver to regulate the body’s vitamin A levels safely. Retinol, however, is pure vitamin A and can easily overwhelm the body. The liver is designed to produce retinol from carotenoids in food, not absorb it directly from extracted oils. Moreover, retinol in cod liver oil can interfere with vitamin D3 absorption, reducing its effectiveness.

Both fish oil and cod liver oil are also linked to a little-discussed disease: yellow fat disease (pansteatitis). This condition affects animals, particularly felines, and can harm the human liver. The liver of any animal—including the cod—is a toxic organ designed to filter poisons and should be consumed sparingly, if at all.

I love fish, but only when they are alive. The industrial-scale harvesting of marine life for oil is wreaking havoc on ecosystems and contributing to climate imbalance. Some tsunamis and earthquakes may even be tied to the cascading effects of human interference in nature.

The reality is uncomfortable: fish oil and cod liver oil are not health elixirs—they are unstable, oxidized, and potentially harmful substances. Our bodies are designed to extract nutrients safely from whole foods, not concentrated, processed oils. It’s time to rethink what we consider “essential” in the pursuit of health.