In a recent media briefing hosted by the Johns Hopkins Bloomberg School of Public Health, two leading experts debunked common myths surrounding seed oils. They offered a critical examination of the rise of ultra-processed foods. The discussion, moderated by Ellen Wilson, featured Dr. Matti Marklund and Dr. Julia Wolfson, who offered evidence-based insights into these highly debated dietary topics.
The Misunderstood Case of Seed Oils
Dr. Matti Marklund, an assistant professor in the Department of International Health, opened the discussion by addressing the widespread online negativity surrounding seed oils. He emphasized their nutritional value, noting their affordability and versatility in cooking.
“They are also an important source of healthy fats, especially linoleic acid, which is an essential Omega-6 fatty acid that the body cannot make on its own and must get from foods,” Dr. Marklund stated.
Contrary to claims from wellness influencers that these oils cause inflammation, Dr. Marklund pointed to a robust body of evidence showing the opposite. “Scientific studies consistently show that higher intake is linked to lower risk of chronic diseases, including heart disease, stroke, and type 2 diabetes,” he explained. “Despite widespread claims online, there is no credible evidence that seed oils or linoleic acid promote inflammation in humans. In fact, research shows the opposite.”
When asked where the “anti-seed oil moment” originated, Dr. Marklund identified social media as the primary source of misinformation. He argued that the backlash is “largely based on misinformation” and that “high-quality research consistently shows that seed oils once consumed in the context of a balanced diet can contribute to improved heart health and overall well-being.”
For primary care physicians advising patients, his message was clear: “Encourage patients to use seed oils like soybean, canola, or sunflower oil, instead of using butter. And that is a simple evidence-based way to support heart health.”
Unpacking Ultra-Processed Foods
Dr. Julia Wolfson, an associate professor in the departments of International Health and Health Policy and Management, tackled the complex issue of ultra-processed foods (UPFs), which now dominate the American diet.
“Today, ultra-processed foods are the majority of the foods that we eat in the United States, and if you picture a typical grocery store, more than 60% of the foods and beverages lining the shelves are ultra-processed,” Dr. Wolfson said.
She distinguished these industrial formulations from traditionally processed foods, such as cheese or canned fish. UPFs, she explained, utilize techniques such as extrusion and molding, and contain additives like emulsifiers and artificial flavors to create “hyper palatable and irresistible” products. Examples range from sodas and packaged snacks to frozen meals and processed meats.
The public health concern is two-fold. First, their sheer volume in the food system is alarming. Second, their consumption is linked to a startling number of health problems. “They’re associated with worse diet quality and a long and growing list of adverse health outcomes, including obesity, type two diabetes… many cancers, gastrointestinal disorders, asthma, anxiety, depression, cardiovascular events and premature all-cause mortality,” she noted.
Dr. Wolfson also highlighted the socioeconomic barriers to reducing UPF consumption, including their convenience, accessibility, and affordability, particularly for food-insecure households. “It just takes more planning and more mental effort to cook a whole meal from mostly scratch ingredients than it does to heat up a frozen dinner, for example, or make a box of macaroni and cheese,” she explained.
One of the biggest misunderstandings, according to Dr. Wolfson, is the belief that all UPFs are simply “junk food.” This oversimplification overlooks the reality that many families rely on more benign UPFs, such as packaged whole wheat bread or soy milk. “They are not all only junk foods that you can just cut out of your diet easily,” she cautioned, arguing for a more nuanced approach in dietary guidelines.
In her closing remarks, Dr. Wolfson called for careful policy-making. “It’s critical that we proceed quickly, but also carefully and thoughtfully to implement policies and public health approaches to reduce ultra-processed food intake in ways that do not adversely and inequitably burden individuals trying their best to feed their families.”
Watch the whole conversation here:
