Oils are a type of plant, animal, or synthetic fat used in cooking, baking, flavoring, and food preparation. The macronutrient composition of oils are comprised 100% of FAT. You’re probably thinking that fat doesn’t sound like a good thing…Well, think again. There are many complex components that make certain fats and oils “healthy” while others are considered “unhealthy”.
Choosing what type of oil to buy and use can be an overwhelming experience. There are so many different options: Vegetable, Olive, Peanut, Soybean, Sunflower, Canola, Corn, Almond, Avocado, Coconut, and Sesame Oil…Which one do you choose and why?
What constitutes as a “healthy oil”?
It is recommended that a healthy diet should be comprised of 25-35% of calories from fat. There are two main types of fats: Saturated and Unsaturated.
SATURATED FAT: Saturated fats come mostly from animal fats and are solid at room temperature. Saturated fats are completely saturated with hydrogen atoms along the fatty acid chain and there are no double bonds between the carbon atoms.
This is considered the “bad” type of fat because it has been shown to increase the risk of heart disease by raising total cholesterol and LDL cholesterol (the “bad” cholesterol).
UNSATURATED FAT: Unsaturated fats come from both animal and plant products and are generally liquid at room temperature. Unsaturated fats contain at least one double bond within the carbon chain. Unsaturated fats can be in either the cis or trans isomer. A cis isomer is when the hydrogen atoms are on the same side of the double bond, whereas a trans isomer is on the opposite side of the double bond. in general, trans fatty acids are unhealthier. Fatty acids have two different ends: the carboxyl end (-COOH) and the methyl end (-CH3).
There are several different types of unsaturated fats:
1.) Monounsaturated fats: Contains 1 double bond. Monounsaturated fats have been shown to reduce the risk of cardiovascular disease by decreasing LDL cholesterol (the “bad” cholesterol).
2.) Polyunsaturated fats: Contains 2 or more double bonds.
- Omega-3 fatty acids: This is an essential fatty acid from mostly plant and marine/fish sources. It is essential because the human body is unable to synthesize omega-3’s and therefore it must be consumed in the diet. It is considered an omega-3 because the first double bond starts at the 3rd carbon atom from the methyl end of the carbon chain. Omega-3 fatty acids are reported to have several health benefits, which are still under scientific review and debate. The reported health benefits are decreased risk of cardiovascular disease, cancer, inflammation, depression, cognitive decline, arthritis, and dry skin.
- Omega-6 fatty acids: This is also an essential fatty acid with the first double bond starting at the 6th carbon from the methyl end of the carbon chain. Omega-6 fatty acids are reported to have adverse health effects such as increased risk for cardiovascular disease, asthma, arthritis, and certain cancers.
3.) Trans fats: This is an unsaturated fatty acid in the trans position (two hydrogen atoms are on the opposite side of the double bond). Trans fats have different chemical and physical properties that make it valuable in food production, such as increasing the shelf-life of food. However, trans fats have been shown to be one of the “worst” types of fats for the human body. This is because it increases the risk for heart disease by increasing LDL cholesterol (the “bad” cholesterol) and decreasing HDL cholesterol (the “good” cholesterol). Therefore, most leading health organizations recommend consuming as little trans fat as possible or consuming <1% of total energy from trans fats.
Healthy vs. Unhealthy Oils and Uses in Cooking
When choosing an oil, in general try to choose oils that contain more mono and polyunsaturated fats and less saturated and trans fats.
Check out this Cooking Oil Comparison Chart! It categorizes healthy vs. unhealthy oils, and oils better for cooking vs. dressings.
When it comes to choosing a cooking oil in the grocery aisle, you have to take into consideration the health benefits as well as the cooking technique.
Safflower Oil: Safflower oil is high in polyunsaturated fatty acids and low in saturated fat. It is best for medium-heat cooking such as stir-frying or sautéing.
**Canola Oil: Canola oil got it’s name in 1978 as “CANadian Oil, Low Acid”. Canola oil is made from the rapeseed. Canola oil is considered very heart healthy due to it’s low saturated fat, high monounsaturated, and moderate polyunsaturated fat content. Canola oil has a high smoking point and can be used for high-heat cooking, such as frying.
Sunflower Oil: Made from sunflower seeds, this oil has a very high smoke point and is commonly used for frying foods. Even though it has an abundance of polyunsaturated fat and Vitamin E, most of it is unhealthy omega-6 fatty acids and very little healthy omega-3’s. Therefore, this is not the best nor the worst oil to choose from. If you’re looking for something healthy, try canola or olive oil.
Corn Oil: I would stay far away from corn oil. The polyunsaturated content is 98% omega-6 and only 2% omega-3’s. It has a high smoke point and is commonly used for frying. Not worth it.
Peanut Oil: Peanut oil can be used for deep-frying, sautéing, or grilling food. The proposed health benefits of peanut oil is mixed among the research. It has a relatively high saturated fat content compared to most other vegetable oils, but it also has a high poly/monounsaturated fat content. I would probably avoid this oil and stick to one with more definitive research on the health benefits. Plus, many people have allergies to peanuts.
**Olive Oil: Olive oil is used in many Mediterranean and Italian dishes because it is one of the tastiest oils. It is high in monounsaturated fat and is beneficial to heart health. Olive oil has a low smoking point and it used for simmering foods on low heat as well as for dipping/dressings.
Soybean Oil: Soybean oil is high in omega-6 fatty acids and for that reason, it is probably not the healthiest choice. It has a very high smoke point and if you are looking to buy soybean oil, avoid the hydrogenated versions.
Avocado Oil: The fatty acid composition of avocado oil is similar to that of olive oil, and it thus a healthy option. It has a higher smoke point than olive oil and contains loads of monounsaturated fatty acids.
Butter/lard: Bad, bad, bad. High in saturated and probably trans fats. Just stay away from these as much as possible. Try to stick to soft tubs of margarine instead of solid bars of butter/lard.
**These are the healthiest options.
Fat composition of common oils
Fat composition of common foods