Concerns over seed oils continue, with some health experts saying they are a useful source of unsaturated fats. However, others argue that their widespread use may be damaging to health.
Current evidence suggests that seed oils are not toxic and actually have health benefits. Still, their prominent role within the modern food supply remains a topic of ongoing research. For most people, the bigger nutritional concern may be excessive consumption of seed oils in ultra-processed foods. This is rather than seed oils alone.
Seed oils are vegetable oils extracted from the seeds of plants. Common examples include canola oil, soybean oil, corn oil, sunflower oil, safflower oil, cottonseed oil, grapeseed oil and rice bran oil. These oils became popular during the 20th century because they are inexpensive to produce and have a long shelf life. Additionally, they can be used in a wide range of processed foods.
Inflammation and Chronic Diseases
One of the main reasons seed oils have become controversial is their high content of omega-6 fatty acids.
Omega fatty acids are a family of essential fats that play important roles throughout the body. They are called “essential” because the body cannot make them efficiently, so they must come from food. Omega-3s are best known for supporting heart, brain, eye and joint health. Specifically, they help regulate inflammation and are associated with a lower risk of cardiovascular disease. Omega-3s are found in oily fish, flaxseeds and walnuts. Omega-6 fats are also essential and play roles in growth, immune function, skin health and normal metabolism. The balance of Omega-6 and Omega-3 fatty acids is important for health. However, some researchers suggest that modern diets contain far more omega-6 fats than previous generations consumed. At the same time, intake of omega-3 fats has declined. The concern is that an imbalance between omega-6 and omega-3 fatty acids may promote inflammation in the body.
Recent research published in April 2026 shows that the data overwhelmingly support the safety and health benefits of seed oils. This includes benefits not only with respect to cardiovascular disease, but possibly other chronic diseases as well.
However, the way seed oils are often consumed could be a health issue.
They are a major ingredient in ultra-processed foods such as chips, crackers, biscuits, fast food, frozen meals, salad dressings and packaged snacks. These foods tend to be high in calories, sugar and salt. Furthermore, they are often low in fibre and nutrients. Some experts argue that the health problems associated with seed oils may actually reflect the unhealthy foods in which they are commonly found rather than the oils themselves.
Oxidation
High-temperature cooking is another consideration. Some seed oils are rich in polyunsaturated fats, which can be more susceptible to oxidation when exposed to heat, light and air. Oxidation can produce compounds that may be harmful if consumed in large amounts over time. Using fresh oils and storing them properly can help minimise this issue. Additionally, avoiding repeatedly heating the same oil is beneficial.
Ways to reduce your intake of seed oils
For those who wish to reduce their intake of seed oils, the first step is reading food labels. Ingredients such as soybean oil, canola oil, sunflower oil, safflower oil and cottonseed oil appear in many packaged foods. Choosing whole foods instead of highly processed products is often the most effective way to reduce exposure.
Cooking more meals at home can also help. Many restaurants, takeaway outlets and food manufacturers rely on seed oils because they are inexpensive and versatile. Preparing food from scratch allows greater control over the fats used in cooking.
Alternative fats are available for those seeking to avoid seed oils. Extra virgin olive oil is rich in monounsaturated fats and antioxidants and has been associated with numerous health benefits, particularly in Mediterranean-style diets. Avocado oil is another option with a relatively high smoke point. Some people choose butter, ghee or coconut oil. However, these contain higher levels of saturated fat and should be used in moderation according to most dietary guidelines.
Increasing omega-3 intake may also help improve the balance between omega-6 and omega-3 fats. Oily fish such as salmon, sardines and mackerel are excellent sources. Alternatively, flaxseeds, chia seeds and walnuts provide plant-based alternatives.
Ultimately, a diet centred on whole foods, vegetables, fruits, legumes, nuts, quality proteins and healthy fats is likely to have a far greater impact on long-term health than focusing on any single ingredient. Whether you choose to include seed oils or avoid them, prioritising minimally processed foods remains one of the most effective strategies for supporting overall wellbeing. In addition, maintaining a balanced dietary pattern is crucial.
