Walk down the cooking oil aisle of any grocery store, and you’ll find anything from olive, canola, sunflower, coconut, avocado, peanut, sesame oil…the list goes on! These oils all serve their own purpose, but sometimes it can be tough to decide which oil to buy and cook with when most of them have received a ton of criticism over the years. 

Here’s the good news: oils aren’t nearly as scary or *magical* as they’re often made out to be. Each has strengths, weaknesses, and best uses in the kitchen. The key is knowing when and how to use them.

Let’s break it down!

Why Oils Matter

Cooking oils are mostly made of three kinds of fat:

  • Saturated fat (found in butter, coconut oil, palm oil)
  • Monounsaturated fat (MUFA) (olive oil, avocado oil, peanut oil)
  • Polyunsaturated fat (PUFA) (canola, sunflower, soybean, corn oil)

Research consistently shows that swapping saturated fats for MUFAs or PUFAs can help lower LDL (“bad”) cholesterol and support heart health. That’s why organizations like the American Heart Association recommend non-tropical vegetable and seed oils over butter, lard, or coconut oil.

Making the Most of Different Oils

  • Olive Oil (extra-virgin): Rich in flavor and antioxidants, best for salad dressings, drizzling, or low- to medium-heat cooking. Not ideal for super-high heat.
  • Canola, Sunflower, Soybean, Corn Oil: Neutral flavor, affordable, and versatile for sautéing, roasting, and baking.
  • Avocado Oil: High smoke point + heart-healthy fats = perfect for grilling, roasting, and high-heat stir-frying.
  • Sesame Oil: Distinct nutty flavor, so a little goes a long way. Best as a finishing touch for stir-fries, noodles, and dressings.
  • Coconut Oil & Butter: Adds richness and flavor, but is higher in saturated fat. Use occasionally, more for taste than health benefits.

A Dive Into Seed Oils: What Are They, Anyway?

Seed oils are vegetable oils pressed or extracted from a plant’s seed. Common ones include:

  • Canola
  • Soybean
  • Sunflower
  • Corn
  • Safflower
  • Grapeseed

Unlike olive oil (which comes from the fruit), seed oils are higher in polyunsaturated fats (PUFAs), especially omega-6 fatty acids like linoleic acid. But that doesn’t mean it only has omega-6s. In fact, no oil is just omega-6s. Seed oils still contain a mix of fats: mostly omega-6s, plus some monounsaturated fats, a little saturated fat, and even trace omega-3s.

A Look Into the Research on Seed Oils

Seed oils like canola, sunflower, and soybean often get labeled as “toxic” or “inflammatory.” But here’s what the science says:

  • They’re rich in omega-6 fatty acids (specifically linoleic acid), which some fear causes inflammation. But large studies show higher intake is linked to lower risk of heart disease and type 2 diabetes.
  • The truth: we often eat these oils in ultra-processed foods (fried snacks, fast food, packaged baked goods). Those foods are the real health issue, not the oils themselves.
  • Processing and refining sound scary (hexane! bleaching! deodorizing!), but the leftover solvent levels are negligible and not harmful. The bigger concern is when oils are repeatedly overheated, like in deep fryers.

Essentially, this means that the oil in your homemade stir-fry isn’t the issue. It’s the oil in your fast-food fries.

Tips for Choosing & Using Oils

  • Match the oil to the cooking method. For high-heat cooking, go for avocado, canola, or peanut oil. For dressing a salad, go for olive or sesame oil (adds flavor).
  • Keep it simple. Stock one neutral oil (like canola or avocado) and one flavorful oil (like extra-virgin olive). That combo covers 90% of everyday cooking.
  • Remember the real issue. The fries, chips, and ultra-processed snacks where seed oils show up are the problem, not the oils themselves!
  • Mix it up. No single oil is “perfect.” Variety helps you get a mix of nutrients and flavors.

Bottom Line

Cooking oils don’t need to be confusing, or controversial! Each has its own strengths in the kitchen, and none are inherently “toxic” or “magical.” The science shows that the real problem with seed oils is the way they are prepared and processed, like in ultra-processed foods. All oils can play a role in a healthy diet when used wisely. The key is knowing when and how to use them so you can feel more confident, less stressed, and a lot more excited about cooking at home.