Which oils are best to cook with?

November 05, 2015

You have many options when it comes to selecting fats and oils for cooking. But it’s not just a matter of choosing oils that are healthy, but also whether they stay healthy after having been cooked with.

Canola oil

Canola oil is what comes from extracting the seeds of a canola plant. It’s inexpensive and commonly used in processed foods as well as for commercial frying.

Benefits

As with most liquid oils, canola contains plenty of omega-3 fats, which are the good fats also found in fish. These have anti-inflammatory properties and can help reduce blood cholesterol. Only add this oil to your shopping list if you can get it fresh, locally and from seeds that haven’t been genetically modified.

Downsides

The seeds used to make canola oil can be genetically modified, which some say causes damage to the environment and aren't good for you. Australian manufacturers don’t have to label their products accordingly, so it’s impossible to know if the seeds are organic or not.

What’s more, the omega-3 fats in canola oil go rancid so its healing powers will depend on how well the canola oil has been kept from production line to kitchen cupboard. A US study also found a link between cooking with canola oil and reduced lung function.

Peanut oil

Peanut kernels are pressed to produce this tasty oil, which is often the pick for frying because it doesn't absorb a food’s flavor.

Benefits

Peanut oil has a lot going for it, Stanton says it keeps well, cooks well and ranks well in the polyunsaturated and monounsaturated fat stakes, meaning it’s beneficial for blood cholesterol and heart health. Enjoy it in moderation but aim for healthier options.

Downsides

It has more saturated fat than olive, avocado, sunflower and sesame oils, and can be quite expensive.

Avocado Oil

The composition of avocado oil is similar to olive oil. It is primarily monounsaturated, with some saturated and polyunsaturated mixed in.

It can be used for many of the same purposes as olive oil. You can cook with it, or use it cold.

Coconut oil

The kernels of older coconuts are extracted to make this on-trend oil.

Benefits

Eating coconut oil can increase the good cholesterol in your blood and its stable at high temperatures, making it perfect for cooking. “It produces a crispy bickie,” Stanton says. Resist eating it by the spoonful straight from the jar. If you’re keen for a coconut hit, get your hands on the real thing. “Kale and green smoothies are great but please leave out the coconut oil,”

Stanton says.

Downsides

It might taste like a tropical paradise but 1 tsp of coconut oil has almost 4g of saturated fat. That’s a significant chunk of the 24g recommended daily by the Dietitians Association of Australia. “I know it’s trendy and it does help your [good] cholesterol a bit, but it raises bad cholesterol much more,” Stanton says. “A little won’t hurt but coconut oil is a food for which the evidence is only bad.”

Palm oil

This red-tinged oil is made by pressing the fruit of oil palm trees.

Benefits

Palm oil can withstand high temperatures and is cheap to produce, which is why it’s commonly used for commercial frying and found in a lot of processed foods. Try to avoid having this oil as much as possible. “The awful thing is you don’t know where it comes from or which foods it’s in so it’s difficult to steer clear of,” Stanton says.

Downsides

It’s high in saturated fat and offers little nutritionally. Most importantly, Stanton says, its production is environmentally disastrous. The industry has been linked to deforestation, habitat destruction, animal cruelty and human rights abuses.

Sunflower oil

As if the beauty of sunflowers wasn't enough, their seeds are compressed to make this helpful oil.

Benefits

This golden liquid is high in vitamin E, which plays a key role in supporting the immune system and has also been linked to preventing memory disorders, improved lung function and slowing the decline of people with Alzheimer’s. “You’ll also find those fats that are good for reducing cholesterol and keeping your heart healthy,” Stanton says. It keeps well and is inexpensive. Keep it in the cupboard as an alternative to extra virgin olive oil, but don’t reuse it too often.

Downsides

Sunflower oil retains its nutritional goodness at high temperatures, but reusing it too many times which is common thanks to its effectiveness at frying can cause harmful Trans fats to form.

Olive oil

Olives are crushed and the oil is filtered and bottled. It’s best fresh and should smell a bit like green grass.

Benefits

“Extra virgin olive oil is far and away the best oil they don’t come any better,” Stanton says. The reasons are abundant and so is the supporting research. As well as boasting healthy fats that help reduce cholesterol and improve heart health, olive oil has been proven to lower blood pressure.

“There have been a lot of myths about olive oil, the biggest being that you can’t cook with it,” Stanton says. In fact, she adds that an Australian study recently proved that extra virgin olive oil has a higher smoke point (the temperature at which it smokes and starts to burn, releasing potential carcinogens) than both butter and canola oil. Part with a couple more dollars to take home a bottle of fresh, Aussie, extra virgin olive oil. Then enjoy it in, on and with whatever you please.

Downsides

Olive oil is one of the more expensive oils. If you’re opting for anything other than extra virgin, your cholesterol levels will still benefit but those other protective powers will be diminished.