Not all fats are bad for us. Michelle Gelok looks at the health benefits and downsides of common cooking oils
For years, low-fat cooking was considered the cornerstone of healthy eating, but it's now clear that fat is not the dietary villain it was once thought to be. When it comes to healthy cooking, it turns out what matters most is the type of fat we eat, rather than how much. But not all cooking oils are created equal. Here is a guide to the health pros and cons of the most common.
Olive oil is the darling of all the cooking oils - and with good reason. Olive oil has the highest concentration of heart-healthy monounsaturated fat, which can help lower LDL, the bad cholesterol, and raise HDL, the good cholesterol.
But its health benefits don't end there: olive oil also contains potent phytochemicals and antioxidants that are thought to dilate blood vessels, prevent blood clots and decrease inflammation in the body. What's more, just last month a groundbreaking study published in the journal Neurology found that older adults who used the most olive oil in their diet had a 41 per cent lower risk of stroke, compared with those who never use the oil in their diet.
The only downside to olive oil is its low smoke point, a measure of how quickly fat molecules break down when exposed to heat. Not only can heating olive oil negatively affect its flavour, it can also produce harmful chemicals called free radicals. For this reason, it's best to use olive oil in salad dressings and to season cooked foods, such as pasta, fish or vegetables.
For years, coconut oil has been vilified for its unusually high saturated fat content, a type of fat that is dominant in animal foods, and can have a detrimental effect on cholesterol levels. Its unhealthy fat profile has encouraged some health organisations to suggest limiting its intake: the American Heart Association recommends limiting tropical cooking oils, such as coconut oil, to help reduce the overall amount of saturated fat in the diet.
But new evidence is helping coconut oil shake its unhealthy reputation. Research now shows that not all saturated fat is created equal and while coconut oil probably raises LDL cholesterol to some extent, it may also increase HDL cholesterol. In fact, a study released earlier this year in the Asia Pacific Journal of Clinical Nutrition found that among Filipinas, the consumption of coconut oil was positively associated with HDL cholesterol levels.
While coconut oil may not be as unhealthy as once thought, it hasn't exactly earned health-food status. Its real health benefits and risks have been clouded by unsubstantiated claims that it is something of a miracle food and can assist with everything from weight loss to treating and preventing diabetes. Until evidence can prove otherwise, coconut oil is best enjoyed in moderation.
Though it doesn't often get touted as such, canola oil is actually one of the healthiest cooking oils around, thanks to its excellent fat profile. Aside from containing the least amount of saturated fat of all the common cooking oils, canola oil contains considerable amounts of the omega-3 fatty acid alpha-linolenic acid (ALA), which has been shown to lower blood pressure and reduce inflammation in the body.
Studies show that substituting canola oil for other fats in the diet is an easy way to healthier eating. In fact, one study published in the Journal of the American Dietetic Association found that swapping canola oil and canola-based margarine for other oils and spreads in the diet, such as butter, helped study participants reduce their saturated fat intake by 10 per cent and increase their ALA intake by 73 per cent.
Canola oil has been dogged by rumours that it's toxic to human health. The rumours probably stem from the fact that canola oil is often confused with rapeseed, a plant that contains high levels of erucic acid, a substance that is toxic to humans in large quantities. The truth is canola oil isn't toxic, in fact the evidence for canola oil's heart-health benefits has been so convincing, the US Food and Drug Administration has approved a health claim stating that when it's used to replace saturated fat in the diet, canola oil can reduce the risk of coronary heart disease.
Palm oil is one of the most popular cooking oils in Africa, south-east Asia and parts of South America because it's both affordable and readily available. Like coconut oil, palm oil is a tropical oil and is very high in saturated fat, particularly palmitic and myristic acid. Palm oil is used extensively in packaged and processed foods, where it's often used to replace partially hydrogenated vegetable oil, a main source of trans fat.
Though not as unhealthy as partially hydrogenated oil, it's thought that palm oil still promotes heart disease. In fact, the World Health Organisation has warned that there is "convincing evidence" that myristic and palmitic acid contribute to an increased risk of heart disease.
Health risks aside, there are also concerns about the environmental impacts of palm oil production. According to World Wildlife Fund Australia, palm oil plantations are a major cause of deforestation in south-east Asia. According to the Centre for Science in the Public Interest, more healthful substitutes are available for palm oil, and where palm oil's use is unavoidable, the organisation suggests obtaining it from environmentally sound sources.
Sunflower oil dominates store shelves here in the UAE, and the good news is it's relatively healthy, especially when it's used to replace less healthy oils in the diet.
While it doesn't have quite the same health benefits as olive and canola oil, it's still an all-round good choice because of its healthy fat content, low cost and the fact that it's suitable for cooking at high temperatures. Sunflower oil contains relatively little saturated fat, but unlike olive and canola oil, which are rich in monounsaturated fat, sunflower oil is mostly polyunsaturated fat. Some studies show polyunsaturated fat, such as sunflower oil, is effective at reducing LDL cholesterol levels by as much as 22 per cent when used to replace sources of saturated fat in the diet, such as butter or ghee.
Sunflower oil also outshines all other cooking oils when it comes to vitamin E, an antioxidant that has been shown to protect against heart disease and age-related macular degeneration. In fact, one tablespoon delivers 6mg of vitamin E, more than half a day's worth for adults.