There is a plethora of conflicting information regarding which oils and fats are healthy, or not, to use in cooking. This is a question that I get asked a lot so I’ve written a brief summary which I hope you’ll find useful as a guideline:
Saturated fats and oils for high heat cooking (can safely be used at all temperatures and raw)
Saturated fats are ‘stable’ fats. I won’t go into the science here, but in short, it has to do with their molecular structure, more specifically their number of hydrogen atoms (i.e whether ‘saturated’ with hydrogen atoms or not, ‘unsaturated’) which dictates whether or not they are denatured by heat. As saturated fats are not chemically altered when cooked this makes them the safest oils to cook with at high temperatures.
They are solid at room temperature: coconut oil, ghee (clarified butter), palm oil, palm kernel oil. Non-vegetarian sources include duck and lamb fat among others.
Unsaturated fat for low / medium heat cooking or to be eaten raw: Unsaturated fat can be divided into monounsaturated fat and polyunsaturated fat. Let’s look at each of these separately.
Monounsaturated fats (MUFAs) are liquid at room temperature but solid in cold temperatures – like olive oil which hardens if you place it in the fridge. Not that you would. The fact that their consistency, and therefore molecular structure changes means that these fats are less stable than saturated fats, oxidising at high temperatures. This makes them suitable for medium heat cooking only and to be eaten raw. Butter, although a saturated fat, has a low smoke point which means that it is suitable for cooking at medium temperatures only (organic butter from grass-fed cows is your best option if you can find it).
Polyunsaturated fats (PUFAs) remain liquid at all temperatures. This category of fats is unstable and not suitable for cooking but are most beneficial added to foods as a dressing. These oils should be bought cold-pressed to ensure that the oil has not been heated during the friction of some extraction processes as this would make them go rancid quicker and oxidise.
The oils we are talking about here are vegetable oils (sunflower, safflower, canola, soy, corn, cottonseed, sesame), nut oils and flaxseed oil.
Essential Fatty Acids (EFAs) omega-6 (linoleic acid – LA) and omega-3 (alpha-linolenic acid – ALA) are polyunsaturated fats. Our modern diets are heavily biased towards omega-6 oils vegetable oils with a ratio up to 20:1 instead of an ideal around 2:1. The importance of achieving a healthy balance is a post in itself. Suffice to say, a healthy start would be to:
drastically reduce or ideally cut out use of vegetable oils as these are highly processed and if they are not already by the time they reach your kitchen, are easily oxidised by heat, air, light which turns them rancid very easily.
use nut oils such as walnut oil sparingly.
using a couple of teaspoons of flaxseed oil (a rich source of omega-3) in salad dressings, for example, is a highly beneficial addition to a healthy diet. Ensure that this is stored appropriately in a dark container in the fridge and used within a few weeks to prevent it from becoming rancid.
Margerine and hydrogenated fats are man-made and definitely do not belong on your dinner plate. Ever.
Our bodies need fat
Be informed and use healthy fats and oils appropriately and in balance as an essential part of a varied diet. And we mustn’t forget to mention that fats and oils contribute to the important element of taste and satiety in our meals. Enjoying our foods with rich flavours and textures is essential to the art of eating well.
How do you incorporate healthy fats and oils into your meals? Have you ever tried making your own ghee?
Fats that heal, Fats that kill – Udo Erasmus