Seed oils — such as soybean, corn, canola, sunflower, and safflower oils have come under increasing scrutiny for their potential role in driving chronic diseases.
These oils are high in omega-6 polyunsaturated fatty acids (PUFAs), particularly linoleic acid, which in excess can contribute to chronic inflammation in the body.
While some omega-6 fats are essential in small amounts, the modern Western diet often contains an imbalanced ratio of omega-6 to omega-3 fatty acids sometimes as high as 20:1 — whereas evolutionary diets had closer to a 1:1 ratio. This imbalance promotes inflammatory processes that are linked to conditions such as heart disease, obesity, diabetes, autoimmune disorders and cancer.
Moreover, the industrial processing of seed oils can involve high-heat extraction and chemical solvents like hexane can degrade the oil and produce harmful byproducts, including trans fats and oxidised lipids. These unstable compounds can generate oxidative stress and cellular damage when consumed regularly, contributing to metabolic dysfunction over time.
Animal and observational studies have shown correlations between high intake of linoleic acid and increased markers of oxidative stress, insulin resistance, and fatty liver disease. Existing evidence has led many researchers and health advocates to caution against the overconsumption of refined seed oils, urging a return to more traditional fats such as olive oil, butter, or coconut oil.