When it comes to seed oils, there is a widening gap in the nutritional conversation. Online discussions about the use of sunflower, soybean and rapeseed oils for daily cooking are divisive to say the least.
On one side are decades of controlled trials, cardiovascular guidelines and a scientific consensus with relatively little internal disagreement. On the other, an online movement convinced that a category of cooking oil used in kitchens for generations is linked to chronic disease.
As the anti-seed-oil movement gains momentum in the UAE, The National speaks with experts about two conversations that have become “remarkably disconnected”.
What are seed oils?
Seed oils are vegetable oils extracted from plant seeds. High in unsaturated fats, particularly linoleic acid – an omega-6 fatty acid – they include sunflower, corn, soybean, rapeseed (also sold as canola), sesame and cottonseed oils.
They appear in home kitchens, restaurant cooking and the vast majority of packaged food. That last fact is, in part, what has made them an easy target.
What the research says
The scientific case for seed oils rests on their fat composition. Oils such as sunflower and rapeseed have been studied in long-term controlled trials for their effects on cardiovascular health. The studies consistently find that replacing saturated fats with unsaturated ones lowers LDL cholesterol (low-density lipoprotein cholesterol, which can build up as plaque on blood vessel walls) and reduces the risk of heart disease.
Idrees Mughal, a nutritionist and science communicator with a large online following built on debunking nutritional misinformation, says 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, agrees. “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,” she says. “In fact, many commonly used seed oils, such as sunflower, rapeseed and soybean, contain unsaturated fats that are considered more heart-friendly than saturated fats when used in appropriate amounts.”
The inflammation argument
The central claim against seed oils – and the one most widely shared online – is that they drive chronic inflammation. The argument rests on the fact that linoleic acid, an omega-6 polyunsaturated fatty acid found in seed oils, can be converted in the body to arachidonic acid, a molecule involved in inflammatory signalling. The leap seed-oil critics make is from that individual reaction to population-level disease.
“It sounds biologically plausible,” says Mughal. “But when researchers actually give people more seed oils in controlled trials, there is no evidence that it increases inflammatory markers. In fact, several controlled trials show them to be anti-inflammatory.”
Mughal describes the wider argument as “mechanistic storytelling”.
“Omega-6 fatty acids can participate in biochemical pathways involved in inflammation, so the story becomes: omega-6 equals inflammation, seed oils contain omega-6, therefore seed oils cause inflammatory disease.
“Human biology just isn't that simple, and controlled trials don't support that conclusion,” he explains.
How the myth takes hold
The anti-seed-oil narrative is particularly compelling because seed oils are common in ultra-processed foods, many of which have been linked to poor health outcomes.
“If someone stops eating crisps, takeaway food, biscuits and other calorie-dense foods containing vegetable oils and feels better or loses weight, they may attribute that improvement to removing seed oils,” says Mughal. “But they've simultaneously changed dozens of other aspects of their diet. That doesn't demonstrate that the oil itself was the problem.”
Dr Thomas attributes the misinformation to the structure of online health content, since bold, villain-based claims travel further than nuance. “It is much easier to label one ingredient as 'good' or 'bad' than to explain the many factors that influence health, including overall diet, physical activity, sleep, stress and genetics. Content that makes bold or controversial claims also tends to attract more attention online, even when those claims are not supported by strong scientific evidence.”
Mughal agrees. “The 'one ingredient is poisoning you' message is a much more compelling one than explaining substitution analyses, dietary patterns and decades of nutritional epidemiology.”
The scale of belief
The real problem is that the belief has moved well beyond niche wellness communities. Mughal says seed oils are now among the most common nutrition topics he encounters.
“What concerns me is that many people now regard avoiding seed oils as almost synonymous with eating healthily, despite the fact that major cardiovascular guidelines continue to recommend replacing saturated fats with unsaturated fats.”
The scientific consensus and the conversation happening on some parts of social media have become “remarkably disconnected”, he adds.
If someone is avoiding seed oils, the concern then becomes what they’re replacing them with. “Using an unsaturated vegetable oil instead of butter, ghee or another fat high in saturated fat will generally improve the fatty-acid profile of the diet and lower LDL cholesterol, liver fat, inflammatory markers and improve glycemic markers. That matters far more than whether an influencer has put a particular oil on a list of 'toxic' ingredients,” says Mughal.
Which oil to cook with, according to the science
Despite the noise, expert advice on cooking oils is relatively straightforward. “People don't need to obsess over finding a completely 'toxin-free' cooking oil,” Mughal says, adding that extra virgin olive oil leads in terms of its evidence base. “Rapeseed and sunflower oil are also perfectly healthy and affordable cooking oils, and there is no reason to be frightened of soybean or other seed oils, either.”
That doesn’t mean that pouring huge amounts of oil over everything is healthy, he adds. “Oils are calorie-dense, and repeatedly overheating oils during deep-frying is a different question altogether.”
At the end of the day, whether an oil is healthy doesn’t make every food containing it healthy, too. “A doughnut fried in sunflower oil is still a doughnut,” says Mughal. “Judge the overall food and dietary pattern, rather than demonising a single ingredient.”
Dr Thomas similarly believes there is no single perfect cooking oil. “The best choice depends on how you are using it and your dietary habits,” she says. “Rather than worrying about avoiding one particular type of oil, I would encourage people to focus on overall quality. Small, sustainable dietary habits maintained over many years have a much greater impact on health than following restrictive food trends that are not supported by evidence.”
In the meantime, the most useful filter for any health claim circulating online, she suggests, is simple. “It's always worth asking whether advice is based on robust clinical research or simply on personal opinion or anecdotal experience.”
