If you’ve spent any time on social media lately, you’ve probably seen bold claims like “seed oils are toxic” or “seed oils are the reason everyone is inflamed.”
It’s enough to make anyone second-guess what they’re cooking with.
As a dietitian, I want to help you cut through the noise without fear, food rules, or all-or-nothing thinking. Because the truth is a lot less dramatic, and a LOT more nuanced, than the internet makes it seem.
Let’s talk about what seed oils actually are, where the concerns come from, and what the research really says.
What Are Seed Oils?
Seed oils are oils extracted from plant seeds, including soybean, canola, sunflower, and corn oil. They’re commonly used in home cooking, restaurants, and processed/convenience foods.
List of seed oils:
- Canola oil (aka rapeseed oil)
- Corn oil
- Cottonseed
- Grapeseed oil
- Soybean oil
- Sunflower oil
- Safflower oil
- Rice bran oil
- Peanut oil
Many seed oils are refined to improve stability and safety. While “processed” has become a red flag online, processing itself isn’t inherently harmful. In many cases it actually improves food safety and usability.
Foods commonly containing seed oils are the nuts and seeds they are derived from, salad dressings, fast food, fried foods, prepackaged pastries, and other ultra processed foods.
Are Seed Oils Inflammatory?
Seed oils are oftentimes rich in linoleic acid, an omega-6 fatty acid. While omega-6 fats can be involved in inflammatory pathways, large reviews have found that higher linoleic acid intake is not associated with higher overall inflammation in the body. Another review on omega-6 fats and inflammation also supports this.
Seed oils themselves do not cause inflammation. This is especially true when incorporated into a balanced diet rich in omega-3 fatty acids and particularly when they replace saturated fats (like butter) in ones diet. The American Heart Association recommends replacing saturated fats with polyunsaturated fats (like those in seed oils) to reduce cardiovascular risk.
What About Omega-6 vs. Omega-3?
This is where things do get a little tricky. Evidence supports a correlation between overconsumption of omega 6 fatty acids and poorer health outcomes. Enter: the omega-6 to omega-3 ratio.
Most Americans are not consuming enough omega-3 fatty acids which is lending to an imbalance in the omega-6 to omega-3 fatty acid ratio.
So, does that make omega-6 fatty acids inherently or automatically harmful? And what do we actually do with that information in practice?
Increase intake of foods rich in omega-3 fatty acids and whole foods in general.
Truly, a tale as old as time. Social media has made it seem like this is revolutionary or life changing information, but once again the answer is BALANCE, not elimination or restriction.
It’s no secret that the typical American diet could benefit from more whole foods and that being overly reliant on convenience foods and calorically dense, ultra-processed foods is not health promoting.
How to Increase Intake of Omega-3 Fatty Acids
This could be a separate blog post (foreshadowing?), but here are some things I do in my home to promote intake of omega-3 fatty acids:
- add chia seeds to yogurt bowls and smoothies
- consume edamame a couple times a week (or more!)
- consume salmon and/or canned tuna 2-3x per week
Some other foods that contain omega-3 fatty acids are flax seeds, walnuts, fish oil supplements, and even canola oil (a seed oil!)
Increasing omega-3’s could look different for you! I encourage you to work with a dietitian to increase omega-3’s in a realistic way.
Should You Avoid Seed Oils?
There’s no strong scientific reason to avoid seed oils entirely. They are a source of essential omega-6 fatty acids, are not inherently inflammatory, and can support heart health when used in place of saturated fats.
Attempting to avoid seed oils entirely could also make adequate nutrition much harder and THAT will absolutely add unnecessary stress to your body.
A more helpful focus is your overall dietary pattern. Eat a variety of foods, include enough fiber, add more omega-3 fatty acids, and eat a balance of whole and convenience foods.
To find the right balance for you, work with a dietitian. I’m covered by insurance! You can get a free benefits check here.
