Health conscious consumers are increasingly ditching old favourites vegetable and canola oil for trendy alternatives like coconut and peanut oil. But are they any healthier? And how do they compare with other options such as heated olive oil and butter?
The short answer is, it depends. The long version requires a quick lesson in food science.
Fats and Oils = Lipids
Edible fats and oils are all part of the lipid family. Fats, such as butter, are solid at room temperature and oils are liquid; their solidity depends on their chemical makeup.
Both are comprised of triglycerides, which have a glycerol backbone and three fatty acids attached. The fatty acids are the important part of the molecule and can be of different lengths and have different numbers of double bonds. They are organised into three groups:
- Saturated fats are mainly derived from animal products such as meat and dairy. They have no double bonds.
- Monounsaturated fats are found in olive oil, avocados and macadamia nuts.They have one double bond.
- Polyunsaturated fats come from corn, seed and nut oils (omega 6) and seafood (omega 3). They have two or more double bonds.
Fats and oils always include a range of saturated and unsaturated fatty acids. The greater the proportion of saturated fatty acids, the more solid it will be at room temperature.
Why We Need Fats and Oils
Once digested, we use the fatty acids to maintain the function of our body’s cells and cell membranes, in hormones and in neurotransmitters. They’re also important for our skin, hair and nails, and they keep us warm and cushion our internal organs.
Fats and oils are used for energy production and provide the most energy per gram of all the macronutrients (fat 37kJ/g; carbohydrate 16kJ/g; and protein 17kJ/g).
