Updated 19 January 2015

Which oil should you use?

Oils are often considered the bad guys in our diet, yet we need them to prepare the simplest meals. Here’s the lowdown on the most popular types of oils.

The cooking and salad oil shelves in the supermarket can be confusing and downright intimidating.

Aren’t the cheaper ones unhealthy and fattening and the healthy oils prohibitively expensive? Can you use the same oil for frying and in salads? And why should you buy olive oil if sunflower and canola are a lot cheaper – and easier to find?

First the good news: the most popular oils – canola, sunflower, olive and cottonseed – are all beneficial and considered healthy because they’re derived from plants.

Canola oil

This oil is made from the crushed seeds of the Canola plant.

It has the lowest content of unhealthy, saturated fats compared to other vegetable oils and is high in healthy, unsaturated fats. It’s also a source of omega-3 fats and alpha linolenic acid (ALA), which may help to reduce raised triglyceride levels (an unhealthy type of blood fat), while preventing abnormal blood clotting. In this way it helps to cut your risk for cardiovascular disease.

Canola is one of the healthiest oils you can use in cooking. It can be heated with very little deterioration and isn’t very distinctive in flavour, so it doesn’t affect the flavour of other foods.

•    Use it for: all cooking processes that require the heating of oil, including stir frying, shallow-frying and sautéing.
•    Suitable for: dipping or dressings, marinades and salsas.

Sunflower oil

This oil is chemically extracted from sunflower seeds, is high in healthy unsaturated fats and low in saturated fats.

Studies have shown that a balanced diet which includes small quantities of sunflower oil has noticeable cholesterol-reducing benefits, although it’s also been found to lower your good cholesterol levels, if eaten in excess.

Sunflower oil is as healthy as other oils and can be used in moderation.

•    Use it for: sautéing, shallow-frying, baking and preserving. Excellent for making mayonnaise.
•    Suitable for: dressings, marinades and salsas.

Salad oils

The bad news, however, is that not all oils are equal – some are indeed healthier than others and not all of them are suitable for every kind of cooking.

“Including oil in your daily eating plan not only contributes to your total energy intake, it also helps the body to absorb the fat-soluble vitamins such as A, D, E and K,” says Erika Ketterer, a registered dietician. But moderation is key – and you should ideally have a range of oils in your cupboard.

We did some digging to give you a user-friendly guide to cooking and salad oils:

Olive oil

Olive oil has long been known as one of the healthier oils. Some of its beneficial properties include its healthy, mono-unsaturated fat content and its abundant supply of polyphenols – anti-oxidants that may prevent heart disease and stroke and lower blood pressure.

Two processes are used to make olive oil, hence the terms “extra-virgin” and “virgin” oil.
* Extra-virgin oils are of higher quality – the olives are processed within 24 hours of picking. For this reason, they contain more antioxidants than the “virgin” oils.

*“Pure” olive oil, or just “olive oil”, is heavily processed to remove certain flavours and aromas. Although it’s still a good source of healthy fats, it’s been stripped of its antioxidant content.

“The best-tasting olive oils are those that haven’t been refined or subjected to high temperatures during processing,” Ketterer explains.

“Because extra-virgin, cold-pressed olive oils are the least processed, they contain higher levels of antioxidants.”

Hard margarines

Generally, olive oil is rich in mono-unsaturated fats, which can lower “bad” LDL cholesterol levels without lowering “good” HDL levels. It also contains powerful antioxidant compounds called polyphenols, which may help to reduce the blood’s tendency to clot, and slow the onset of atherosclerosis.

It may also reduce the risk of cancer, as it’s packed with vitamin E, a powerful antioxidant.

“You can get the most cardiovascular benefit by using olive oil instead of unhealthy saturated fats like butter, ghee, lard and hard margarines,” Ketterer explains.

But it’s expensive, which is probably why chefs and health experts worldwide consider it a “niche” oil for special use.

Although olive oil can be used in cooking, it’s healthier when used in salads or as a dipping sauce. If you use it in cooking, make sure you heat it at a low or medium temperature to retain the antioxidants.

•    Use it for: dressing salads and dipping bread, or light sautéing of onion and garlic.
•    Not suitable for: shallow-frying, deep-frying, braising and baking.

Cottonseed oil

Extracted from cottonseed, this oil is popular in Australia and has a mild, nutty taste.

Cottonseed oil is rich in healthy, unsaturated fats, particularly omega-6 fatty acids – the essential fatty acid that we do need to get from our diets, but which we all get a tad too much of (in comparison to omega-3 fatty acids, that is). The oil is also relatively high in unhealthy, saturated fats (26%), making it less healthy than olive oil (14% saturated fat) and canola oil (7% saturated fat), for instance.

Animal studies have shown that cottonseed oil could have a positive effect on cholesterol but more research is needed before any firm recommendations can be made. What’s more, the oil is an excellent source of vitamin E.

•    Use it for: sautéing, shallow-frying, deep-frying, and baking.
•    Not suitable for: dressings, marinades and salsas.

A few other oils

•    Avocado oil

Made by crushing and cold-pressing the flesh of ripe avocados, this oil is extremely rich in vitamin E and omega-3 and -6 fatty acids. It’s best used for dipping bread and making dressings, marinades and salsas. When cooking with avocado oil, less oil is required for frying and sautéing as it has a high viscosity (in other words, a little goes a long way).

•    Grapeseed oil

This oil is chemically extracted from the seeds of a variety of grapes. Its profile is similar to that of sunflower oil and it’s also rich in the antioxidant, vitamin E. Grapeseed oil can be used for shallow frying, baking, preserving, and for making mayonnaise. It’s also well suited for dressings, marinades and salsas.

•    Peanut oil

Often used in Asian cuisine, peanut oil is high in monounsaturated fats, making it a heart-healthy option. The oil has a high smoke point, which also makes it ideal for frying. Note, however, that this delicious, flavourful oil should be avoided at all costs when cooking for someone with a nut allergy.

•    Coconut oil

The latest research on coconut oil indicates that it could have a positive effect on cholesterol levels, despite its relatively high saturated fat content (92%). However, there currently just isn’t sufficient evidence to promote this oil as healthy.

•    Palm oil

This type of oil is currently the subject of some controversy. The positive attributes – a high smoking point, a long shelf life and high antioxidant content – cannot be argued. However, nutritional experts are concerned about its high level of unhealthy, saturated fat (40-50% of total fat). So, it should be limited, or even avoided. This counts for palm fruit, palm kernel and refined palm oil. Sources include coffee creamers, tea whiteners, commercially prepared biscuits, crackers and pre-packed microwave popcorn.

A last few tips:

•    Always try to choose oils with a low saturated fat content.
•    Include a variety of mono- and polyunsaturated oils in your diet. Each kind of oil can contribute to a healthy diet.
•    Healthier cooking methods are better than deep-frying. Rather steam, stir-fry, grill or bake your food.

(Photo: Woman buying oil from Shutterstock)


5 reasons to love avocados

2018-10-14 07:00

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