The Omega-6 Explosion

A ratio gone wrong

Your body needs both omega-6 and omega-3 fatty acids. They're essential — you have to get them from food. But the ratio matters. Omega-6 and omega-3 compete for the same enzymes and pathways in your body. Too much omega-6 relative to omega-3 promotes inflammation. Too little, and you lack the building blocks for cell membranes and signalling molecules. For most of human history, we ate them in roughly equal amounts.

Estimates of the ancestral omega-6 to omega-3 ratio range from 1:1 to 4:1. The current ratio in the typical Western diet is somewhere between 15:1 and 20:1. Some estimates go higher. This shift happened almost entirely in the last 100 years, and it's driven almost entirely by one thing: the explosion of seed oil consumption.

The ancestral omega-6 to omega-3 ratio was roughly 1:1. Today it's 20:1. The shift happened in a single century.

Linoleic acid in your body

Linoleic acid (LA) is the primary omega-6 fatty acid in seed oils. Soybean oil is 55% LA. Sunflower oil can be 65%+. Corn oil is about 55%. When you eat these oils, the linoleic acid gets incorporated into your cell membranes and stored in your adipose tissue (body fat). Studies analysing adipose tissue samples from Americans over the last century show that linoleic acid has gone from about 2-3% of body fat in the early 1900s to 18-22% today. That's a roughly tenfold increase.

Why it matters

Linoleic acid, when present in excess, gets converted into oxidised metabolites — including 4-HNE and other aldehydes — that are associated with oxidative stress, inflammation, and cellular damage. These metabolites have been implicated in everything from cardiovascular disease to non-alcoholic fatty liver disease to neurodegenerative conditions. The research is still evolving, but the signal is clear: flooding your body with omega-6 from industrial seed oils is an experiment with consequences we're only beginning to understand.

Dr. Chris Knobbe, an ophthalmologist, has presented compelling data linking the rise in seed oil consumption to the parallel rise in chronic diseases of civilisation — heart disease, cancer, diabetes, macular degeneration, obesity. His thesis is that seed oils are the single most significant dietary change of the last century, and the most underrecognised driver of chronic disease.

Linoleic acid in human body fat went from 2% to 20% in a century. That's a tenfold increase driven almost entirely by seed oils.

The fix is simple

Reducing your omega-6 intake doesn't require a radical diet change. It requires replacing seed oils with traditional fats: butter, ghee, tallow, lard, olive oil, coconut oil, avocado oil. Eat wild-caught fish for omega-3. Avoid packaged foods that list soybean oil, canola oil, sunflower oil, or "vegetable oil" in their ingredients. Your ancestors didn't eat seed oils. You don't need to either.