Seed oils—vegetable oils extracted from plant seeds such as sunflower, soybean and rapeseed—have become the subject of intense debate online, despite a scientific consensus supporting their safety. The oils, high in unsaturated fats, appear in home cooking, restaurant kitchens and the vast majority of packaged foods. Their ubiquity has made them an easy target for online critics.
Long-term controlled trials consistently show that replacing saturated fats with unsaturated fats lowers LDL cholesterol and reduces heart disease risk, according to cardiovascular guidelines. Idrees Mughal, a nutritionist and online health communicator, said the idea that seed oils are inherently harmful "simply isn't supported by the totality of human evidence." Dr. Elizabeth Mary Thomas, a specialist in internal medicine at Medcare Medical Centre in Dubai, agreed that "the current body of scientific evidence does not support the idea that seed oils are inherently harmful when consumed as part of a balanced diet."
The central claim against seed oils circulating online is that they drive chronic inflammation through linoleic acid, an omega-6 fatty acid that the body can convert to arachidonic acid, a molecule involved in inflammatory signalling. When researchers give people more seed oils in controlled trials, however, Mughal said "there is no evidence that it increases inflammatory markers," and several trials show them to be anti-inflammatory. He described the argument as "mechanistic storytelling" that assumes human biology is simpler than it actually is.
The anti-seed-oil narrative gains force because seed oils are common in ultra-processed foods linked to poor health. Mughal noted that people stopping consumption of crisps, takeaway food and biscuits may attribute their weight loss or improved health to removing seed oils, overlooking the dozens of other dietary changes they have made simultaneously. Dr. Thomas attributed the misinformation to online incentives favoring bold, villain-based claims over nuanced explanations of how diet, physical activity, sleep, stress and genetics influence health.
Expert advice on cooking oils is relatively straightforward. Mughal said extra virgin olive oil leads in evidence, while rapeseed, sunflower and soybean oils are "perfectly healthy and affordable." He added that using an unsaturated vegetable oil instead of butter, ghee or other saturated fats will generally improve the fatty-acid profile of the diet and lower LDL cholesterol and inflammatory markers.
