Are seed oils really bad? Nutritionist reveals 5 facts you should know
Seed oils are often blamed for obesity and chronic disease, but are they truly dangerous? A nutritionist shares 5 things you should know before discarding them.
By now, you have probably heard that seed oils are toxic, whether from a viral TikTok video or from US Health Secretary Robert F. Kennedy Jr., who recently claimed Americans are being "unknowingly poisoned" by them. Kennedy pointed out that as seed oils like canola, soybean, and safflower became staples in the American diet, obesity rates also surged. So, he even advised people to ditch seed oils and return to traditional fats like butter and lard. But are seed oils really harming our health, or are we falling for a myth? Nutritionist and certified diabetes educator Dr Archana Batra weighed in and revealed five key facts you need to know before adding or cutting seed oils from your kitchen.
What are seed oils?
Seed oils are plant-based oils extracted from the seeds of crops such as sunflower, canola (rapeseed), safflower, cottonseed, and grapeseed. They are also commonly lumped in with other vegetable oils like soy and corn oil because of similar properties—high in polyunsaturated fats and widely used in cooking and processed foods. These oils are commonly used in home kitchens and the food industry.
5 things you should know about seed oil
1. Do seed oils cause inflammation?
One major criticism of seed oils is that they contain omega-6 fatty acids, which are believed to promote inflammation. But that may not be completely true. Omega-6 fats, like linoleic acid, are essential because our bodies cannot make them and we need them from food. While omega-3s are generally known for their anti-inflammatory effects, omega-6s also play a key role in immune function and cell growth.
In fact, a study in the journal Nutrients linked higher intake of omega-6 fats with a reduced risk of cardiovascular disease. Another review in Advances in Nutrition suggests that omega-6s do not increase inflammation when consumed in recommended amounts.
{{/usCountry}}In fact, a study in the journal Nutrients linked higher intake of omega-6 fats with a reduced risk of cardiovascular disease. Another review in Advances in Nutrition suggests that omega-6s do not increase inflammation when consumed in recommended amounts.
{{/usCountry}}Dr Batra tells Health Shots that the real issue may be an imbalance. A healthy omega-6 to omega-3 ratio is around 1:1 to 4:1. But the typical Western diet skews heavily toward omega-6, with ratios as high as 17:1, which may disrupt immune function or increase inflammation markers. This is also mentioned in a study published in the International Journal of Molecular Sciences. That doesn’t mean omega-6 is bad, but it means we need more omega-3s (think fatty fish, chia seeds, and walnuts) to restore balance.
2. What about linoleic acid?
{{/usCountry}}Dr Batra tells Health Shots that the real issue may be an imbalance. A healthy omega-6 to omega-3 ratio is around 1:1 to 4:1. But the typical Western diet skews heavily toward omega-6, with ratios as high as 17:1, which may disrupt immune function or increase inflammation markers. This is also mentioned in a study published in the International Journal of Molecular Sciences. That doesn’t mean omega-6 is bad, but it means we need more omega-3s (think fatty fish, chia seeds, and walnuts) to restore balance.
2. What about linoleic acid?
{{/usCountry}}Linoleic acid, the main fat in seed oils, can convert into arachidonic acid, a compound involved in inflammation. But only a tiny fraction of linoleic acid becomes arachidonic acid in the body. In fact, a 2019 study published in Nutrients found that moderate intake of linoleic acid was actually linked to a lower risk of cardiovascular disease. So instead of eliminating seed oils, the key is moderation and trying different options.
3. The issue of overuse in ultra-processed foods
Seed oils themselves are not necessarily harmful, but the way they are consumed can be. Most people are not just sauteing veggies in sunflower oil, they are consuming seed oils in ultra-processed foods like chips, pastries, and fried snacks. According to the British Medical Journal, ultra-processed foods now make up nearly 60 percent of the US diet and have been associated with obesity, heart disease, and mental health issues. Seed oils are often just one of many processed ingredients in these products.
4. Repeated heating can be harmful
In restaurant kitchens especially, seed oils are often reheated multiple times in deep fryers, which can cause the oils to break down and produce harmful compounds, including trans fats and aldehydes. Dr Batra advises, "Using seed oils once for home cooking is fine because you use them at moderate temperatures, but avoid reheating. Also, choose high-smoke-point oils like sunflower or canola for stir-frying or baking, which are considered safe.
5. Yes, seed oils have benefits
Despite the controversy, seed oils do offer health benefits. They contain polyunsaturated fatty acids (PUFAs), including both omega-3 and omega-6 fats. According to a study in Advances in Nutrition, these fats can help lower the risk of type 2 diabetes and cardiovascular disease. The American Heart Association also supports the use of plant-based oils as part of a heart-healthy diet.
