8 best and worst oils for your health

Coconut and canola and olive, oh my! Our guide to the best and worst cooking oils helps you make healthy choices that can keep illness at bay and may even increase your longevity.

By Sabrina Rogers-Anderson

Olive oil is good for your heart, but you’ve heard that you shouldn’t cook with it. Some experts say coconut oil is a superfood while others seem to think it’s a death trap. What gives?

Each cooking oil has different properties and benefits that make it suited for specific purposes and some oils leave experts divided. But there is one superstar oil that shines brighter than all the rest.

Understanding cooking oil jargon

Before we look at the pros and cons of common cooking oils, here are a few useful terms:

• Extra virgin: This type of oil is made by cold-pressing the fruit, nut or seed. Because it isn’t treated with heat or chemicals (refined), it tastes better, retains more beneficial nutrients and costs more.

• Light/extra light: Light refers to the flavour of the oil and not the fat or kilojoule content.

• Smoke point: The temperature at which an oil starts to smoke when it’s heated.
  
  
• Monounsaturated fatty acids (MUFAs):  These healthy dietary fats lower “bad” (LDL) cholesterol and reduce the risk of heart disease and stroke. They also make oil more heat-stable and safer to cook with.
  

• Polyunsaturated fatty acids (PUFAs): These include omega-3 and omega-6 fatty acids, which lower blood pressure, cholesterol and blood sugar, protecting us from heart disease and type 2 diabetes. But oils high in PUFAs can create unhealthy byproducts when heated.
  

• Saturated fatty acids (SFAs): Oils rich in saturated fats are heat-stable and great to cook with, but SFAs can increase LDL cholesterol and the risk of heart disease. 

The best and worst cooking oils 

Now that you have the lingo down, here’s the lowdown on 8 common cooking oils.

Olive oil (extra points if it's extra virgin olive oil)

As the star of the Mediterranean diet and other healthy eating plans, olive oil has a host of health benefits - especially when you choose extra virgin varieties.

Packed with monounsaturated fats and chemicals known as phenols - many of which act as antioxidants - olive oil lowers LDL cholesterol, protects against heart disease and reduces inflammation that can accelerate ageing.

There’s also some evidence that it may boost gut health, keep dementia at bay and increase lifespan.

Olive oil has long gotten a bad rap as a cooking oil, with detractors claiming its low smoke point means it produces dangerous byproducts when heated.

But research has shown smoke point has no effect on olive oil’s safety or stability. There’s not much this super oil can’t do!

Best for: Drizzling, salad dressings, marinades, sauteing, stir-frying, frying, grilling, roasting and baking

Overall rating: 10/10

Avocado oil

Avocado oil is creamy with a mild taste. It’s high in monounsaturated fats and vitamins A, B, D and E, with extra virgin versions packing the biggest nutritional punch.

While this oil can be pricier than others, it reduces bad cholesterol levels and protects the heart.

The oleic acid it contains may also act as an anti-inflammatory in the brain and protect it.

Best for: Drizzling, salad dressings, marinades, stir-frying, sauteing, frying, grilling, roasting and baking

Overall rating: 8/10

Sesame oil

A staple of Asian cooking, sesame oil has a distinctive nutty flavour. You only need to use a small amount to elevate the flavour of your dish.

It’s packed with monounsaturated and polyunsaturated fats and has antioxidant and anti-inflammatory effects.

Eating sesame oil can help prevent heart disease, stroke and atherosclerosis (the build-up of fats and cholesterol on the artery walls).

Good for: Drizzling and sauteing at low heat (avoid high temperatures)

Overall rating: 7/10

Flaxseed oil

For a boost of omega-3s, which promote heart and brain health, add some flaxseed oil to your morning smoothie or salad dressing.

But don’t heat this oil because its omega-3 content will disappear and its high polyunsaturated fat content could create harmful byproducts.

Good for: Drizzling, salad dressings and smoothies 

Overall rating: 7/10

Coconut oil

Superfood or poison? The answer lies somewhere in between. With 80 to 90% of fat in coconut oil being saturated, some experts caution it could cause heart disease.

But some studies have shown that not all saturated fats are created equal and coconut oil can safely be consumed in moderation as part of an overall healthy diet.

On the other end of the spectrum, coconut oil is often touted as a miracle food that will reduce belly fat, protect the heart and ward off dementia.

While medium chain triglycerides (MCTs) found in some specially formulated coconut oils may have some of these effects, most commercially available versions don’t contain anywhere near the amount of MCTs required to claim these health benefits.

The bottom line? Enjoy small amounts of coconut oil if you like its distinctive taste and texture.

Good for: Sauteing, stir frying and baking (naturally refined coconut oil); smoothies, coffee and raw desserts (unrefined/organic coconut oil)

Overall rating: 5/10

Canola oil

Also known as rapeseed oil, canola oil was developed by Canadian scientists in the 1970s. 

Although it’s low in saturated fat (7%) and high in MUFAs (63%), many of these nutrients are lost in the refining process. While cold-pressed (unrefined) canola oil exists, it can be expensive and hard to find.

Some experts have expressed concern about the fact that canola oil is extracted using a solvent called hexane, but others believe the trace amounts of hexane found in the oil are unlikely to be harmful. 

The benefits of canola oil include its stability at high temperatures, light flavour and affordable price.

Good for: Stir frying, sauteing, searing, grilling, roasting, cooking at high temperatures and baking

Overall rating: 5/10

Vegetable oil

This catch-all term refers to any oil derived from a plant, but most oils that are labelled “vegetable oil” are made from soybeans, canola oil or a blend of these or other cheap oils.

Vegetable oils are highly refined and stripped of valuable nutrients. Because they’re high in polyunsaturated fats, they can produce byproducts such as aldehydes when heated that can cause inflammation and health issues over time. 

They often come from genetically modified crops and the herbicides used to grow them can have a negative impact on the environment and our health.

But vegetable oil is inexpensive and has a neutral flavour, so it’s a popular choice for cooking.

Good for: Sauteing, grilling, frying, roasting and baking

Overall rating: 3/10

Grapeseed oil

Although grapeseed oil is very high in polyunsaturated fats, they’re mainly omega-6 fatty acids. Western diets already include too much omega-6, which can lead to heart disease, cancer and other health conditions when consumed in excess.

Like vegetable oil, it’s highly processed and low in nutrients. 

Good for: Sauteing, grilling and stir frying

Overall rating: 3/10

A cut above the rest

While some oils may be useful for specific purposes or flavours, olive oil is by far the best all-rounder for everything from drizzling to frying and its long list of health benefits speaks for itself.