Seed Oils: Should You Avoid Them? A Practical Look at What Really Matters

If you've spent any time on social media lately, you've probably heard someone say:

"Seed oils are toxic."

Then you turn over the bottle of salad dressing in your refrigerator and see soybean oil or canola oil listed as the first ingredient.

Uh-oh.

Do you throw it away?

Before we turn another food into something to fear, let's look at this more carefully.

The conversation around seed oils is much more nuanced than "good" versus "bad." And, as with so many things in nutrition, the bigger picture matters.

What Exactly Is a Seed Oil?

Seed oils are oils extracted from plant seeds. Common examples include:

• Soybean oil

• Corn oil

• Canola oil

• Cottonseed oil

• Sunflower oil

• Safflower oil

• Grapeseed oil

• Rice bran oil

Many of these oils contain significant amounts of linoleic acid, an omega-6 polyunsaturated fatty acid.

And here's an important point:

Omega-6 fatty acids aren't inherently bad.

Linoleic acid is actually an essential fatty acid, meaning our bodies need it and cannot make it themselves.

So where does the concern come from?

Look at the Bigger Picture

Seed oils are inexpensive, shelf-stable, and versatile, which means they're found in an enormous number of ultra-processed foods.

Look at the labels on:

• Chips and crackers

• Packaged baked goods

• Mayonnaise

• Sauces

• Frozen foods

• Fast food

• Fried restaurant foods

• Commercial salad dressings

And that's where I think this conversation becomes much more useful.

Rather than worrying about the occasional teaspoon of canola oil, look at how frequently ultra-processed foods are showing up in your diet.

If soybean, corn, canola, or another refined oil appears in your breakfast, lunch, snacks, dinner, and restaurant meals, that's very different from consuming it occasionally.

Processing and Heat Matter

Polyunsaturated fats are more susceptible to oxidation than some other fats, particularly when exposed repeatedly to high temperatures.

That's one reason I'm much more interested in helping someone reduce frequently eaten deep-fried and ultra-processed foods than making her afraid of every drop of seed oil she encounters.

Restaurant frying oils, for example, may be heated for prolonged periods or repeatedly used.

That's a very different situation from occasionally consuming an oil as part of an otherwise nutrient-rich meal.

Context matters.

What About Omega-6 and Inflammation?

You'll often hear that omega-6 fats automatically cause inflammation.

The science isn't quite that simple.

Omega-6 and omega-3 fatty acids participate in important biological pathways, and both are needed by the body. Human research has not established that simply eating more linoleic acid inevitably causes chronic inflammation.

Instead of obsessing over achieving a perfect omega-6-to-omega-3 ratio, consider something much more practical:

Eat fewer ultra-processed foods and intentionally eat more omega-3-rich whole foods.

Try including foods such as:

• Salmon

• Sardines

• Mackerel

• Chia seeds

• Ground flaxseed

• Walnuts

Don't Be Afraid of Nuts and Seeds

A handful of walnuts isn't the nutritional equivalent of a bag of fried chips simply because both contain omega-6 fatty acids.

Whole nuts and seeds also provide fiber, protein, vitamins, minerals, and antioxidants.

Once again, we come back to a very simple principle:

Choose whole foods more often.

Salad Dressing: An Easy Place to Start

Here's a small experiment for you.

Go to your refrigerator and turn over your bottle of salad dressing.

What's the first ingredient?

Many bottled dressings use soybean, canola, sunflower, or other vegetable oils.

Does that mean you can never eat bottled dressing again?

Of course not.

But if salad dressing is something you eat almost every day, this is an easy opportunity to make a small change.

And homemade dressing is surprisingly simple.

You don't need a culinary degree. Most vinaigrettes take about two minutes to make.

Here are three to try.

Easy Balsamic Vinaigrette

Ingredients

• ¼ cup extra-virgin olive oil

• ¼ cup balsamic vinegar

• 1 tablespoon honey

• 2 teaspoons Dijon mustard

• 1 garlic clove, minced

• ¼ teaspoon kosher salt

• Pinch of freshly ground black pepper

Directions

Add everything to a small bowl or jar. Whisk until combined or put the lid on the jar and shake well.

That's it!

Fresh Lemon Vinaigrette

Ingredients

• ⅓ cup olive oil

• ¼ cup fresh lemon juice

• 1 teaspoon Dijon mustard

• ½ teaspoon honey or maple syrup

• 1 garlic clove, minced

• Salt and pepper to taste

Directions

Add all ingredients to a small bowl and whisk until emulsified.

Or use my favorite shortcut: put everything in a small jar, tighten the lid, and shake!

Homemade Ranch Dressing

Ingredients

• ½ cup sour cream

• ½ cup mayonnaise made with olive or avocado oil

• ⅓ cup buttermilk or whole milk

• 1 teaspoon apple cider vinegar

• 1 teaspoon dried dill

• ½ teaspoon dried parsley

• ½ teaspoon garlic powder

• ½ teaspoon onion powder

• ½ teaspoon fine sea salt

• Pinch of ground black pepper

Directions

Whisk everything together in a small bowl until smooth. Add a little more buttermilk or milk if you prefer a thinner dressing.

A label-reading note: If reducing seed oils is your goal, check your mayonnaise. Many conventional brands use soybean or canola oil as their primary oil. Look for one made primarily with avocado or olive oil.

These recipes are taken from one of my favorite sites for good homemade foods: Downshiftology.com

Don't Make This Another Food Rule

This might be the most important part of the conversation.

I don't want you leaving the grocery store thinking:

"Great. One more thing I'm not supposed to eat."

That's not the goal.

Instead, ask:

"Where is one place I could choose a less-processed option?"

Maybe it's making your salad dressing this week.

Maybe you buy plain nuts instead of an ultra-processed snack.

Maybe you cook dinner with extra-virgin olive oil rather than ordering something fried.

Maybe you add salmon to your dinner this week.

That's enough.

You don't have to clean out your entire kitchen today.

The Bottom Line

Seed oils aren't poison, and there's no reason to fear whole foods like nuts and seeds because they contain omega-6 fats.

At the same time, refined oils are widespread in the ultra-processed and repeatedly fried foods many of us eat frequently.

So rather than obsessing over one ingredient, zoom out.

Eat more whole foods.

Cook at home more often.

Use extra-virgin olive oil and other appropriate cooking fats.

Eat omega-3-rich foods regularly.

Read ingredient labels.

And make simple swaps where they make sense for your life.

Start with the salad dressing if you'd like.

One jar.

Two minutes.

One small change.

That's how we build better health—not through fear and perfection, but through small choices we can actually repeat.

💚 Renew Nurse Health Coaching

Helping women build consistent, sustainable habits for lifelong wellness—one small step at a time.