A new scientific study has overturned a widespread dietary myth, revealing that consuming seed oils like soybean and corn oil may actually lower inflammation and improve heart health—contrary to persistent claims suggesting otherwise. The findings, presented at the prestigious NUTRITION 2025 conference in Orlando, Florida, are highly relevant for Thai consumers amid ongoing debates about cooking oil safety and chronic disease in the Kingdom.
Seed oils, including commonly used vegetable oils rich in linoleic acid—a type of omega-6 fatty acid—have become controversial, with vocal critics suggesting they may promote inflammation and contribute to the country’s rising rates of heart disease and diabetes. These oils are common kitchen staples in Thai households and are found in a variety of popular foods, from street-side stir fries to commercial packaged snacks.
But the latest research, led by an adjunct professor at the Indiana University School of Public Health-Bloomington and chief scientist at Midwest Biomedical Research, is upending these fears. The team assessed nearly 1,900 individuals drawn from a Covid-19-focused observational cohort. Instead of relying on self-reported dietary intakes, the researchers measured actual blood plasma levels of linoleic acid, providing a more accurate indicator of seed oil consumption. According to the lead researcher, “There has been increasing attention on seed oils, with some claiming these oils promote inflammation and raise cardiometabolic risk. Our study… found that higher linoleic acid in blood plasma was associated with lower levels of biomarkers of cardiometabolic risk, including those related to inflammation.”
The research showed a strong association: participants with higher plasma linoleic acid also had significantly lower readings for key risk factors linked to cardiovascular disease and type 2 diabetes. This includes lower glucose and insulin levels, a reduced HOMA-IR score (a marker of insulin resistance), and decreased concentrations of inflammation biomarkers such as C-reactive protein, glycoprotein acetyls, and serum amyloid A. “We saw consistent results across the different biomarkers measured,” said the lead researcher. “People with higher levels of linoleic acid in their blood tended to have a healthier overall risk profile for heart disease and diabetes.”
These results not only reinforce earlier observational studies tying greater linoleic acid intake to reduced risks of type 2 diabetes and heart attacks, but also advance the science by using objective blood measurements instead of dietary questionnaires, which are susceptible to recall errors and bias. This methodological rigour adds weight to the findings and should help reassure consumers wary of modern seed oils.
The implications for Thailand are significant. Urban lifestyles and shifting food preferences have raised concerns over “Westernized” diets and processed food ingredients, particularly among health-conscious Thais. Misinformation online—fuelled by international social media trends—has led some consumers to fear all seed oils, despite their widespread use in Thai cuisine and official endorsements by Thai health authorities. In fact, the World Health Organization and leading Thai health agencies have long recommended replacing saturated animal fats with unsaturated plant oils—especially those high in linoleic acid—as a strategy to prevent cardiovascular disease (World Health Organization). Nevertheless, the debate over the dangers of so-called “ultra-processed” oils continues.
Nutrition experts around the world and in Thailand stress that context matters. Not all fats are equal: unsaturated fats—like linoleic acid from seed oils—can be health-promoting, especially when they replace saturated fats from sources such as lard and palm oil, which are still common in certain Thai dishes. This latest study, as emphasized by the research team, supports not just the safety, but the potential benefits, of linoleic acid when included as part of a balanced diet rich in plant foods and vegetables, staples of Thai cuisine.
Yet, caution is advised against overinterpretation. As the study authors note, while the associations are compelling, causality cannot be definitively established from cross-sectional data alone. Intervention studies—where participants’ diets are changed under controlled conditions—are needed to confirm whether increasing linoleic acid intake directly improves heart and metabolic health. The research team has stated their intention to pursue such studies, including comparisons between different oil types with varying fatty acid profiles, which could provide more personalized dietary recommendations in the future.
For Thai readers, it’s important to recognize the complex interplay between diet, genetics, lifestyle, and chronic disease. Thai cuisine naturally features a diversity of herbs, plant oils, and fresh vegetables—factors supported by international and domestic research for promoting long-term health (Ministry of Public Health of Thailand). Local nutritionists from the Ministry of Public Health frequently advise that moderation, variety, and an emphasis on whole foods are far more important than demonizing any one ingredient. “Seed oils are an efficient way to get healthy unsaturated fats in our diets. What matters most is the overall pattern of eating and the balance of food choices, not fixating on a single oil or nutrient,” a Bangkok-based public health official commented in a previous interview.
Historically, Thailand has faced its own unique nutritional challenges: from widespread malnutrition in previous generations to the present-day epidemic of obesity and cardiovascular illnesses (Bangkok Post). These transitions mirror changes in agricultural production, food imports, and global dietary influences. The increasing popularity of plant-based and alternative diets in urban centres might further highlight the relevance of this study, as more Thais experiment with various cooking oils and health claims found on supermarket shelves.
Looking ahead, the research findings could inform future Thai public health campaigns, particularly those addressing chronic inflammation, a key driver of heart disease and diabetes. They also highlight the need for clearer communication between scientists, healthcare providers, and the public—countering online myths with rigorously tested evidence. As food trends evolve and more health products appear on the market, Thai consumers are encouraged to scrutinize sources and prioritize guidelines from recognized authorities over celebrity or influencer nutrition advice.
In practical terms, Thais seeking to improve their heart and metabolic health should focus on including more plant-based foods and healthy unsaturated fats, such as those from traditional seed oils, soybeans, and nuts, while minimizing saturated fats from animal sources. As always, applying the wisdom of moderation—‘kin pordee’ (กินพอดี)—remains central to Thai cultural attitudes toward eating. Continued investment in nutrition education and transparent scientific research will be vital to navigating the challenges and opportunities of modern food environments.
For those interested in further reading, the study was released via ScienceDaily with additional commentary provided by the American Society for Nutrition. Thais are encouraged to consult updates from the Ministry of Public Health and major hospital networks for recommendations tailored to local health needs.