There is many options when it comes to choosing oils or other fats for cooking but its not only the matter of picking the healthiest but also the oils that stay healthy after having been cooked with. When you’re cooking at a high heat, its best to use oils that are stable and don’t oxidise or go rancid easily. When oils undergo oxidation, they react with oxygen to form free radicals and harmful compounds. Saturated fats and monounsaturated fats are resistant to heating, but oils that are high in polyunsaturated fats aren’t and can become oxidised and rancid at higher temperatures.

Saturated fats:

Coconut oil

Coconut oil contains a large proportion of lauric acid, a saturated fat that raises total blood cholesterol levels by increasing both the amount of high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol. Although this can create better blood cholesterol profile, overconsumption may increase the risk of cardiovascular disease so this oils should be enjoyed in moderation.

Because the majority of saturated fat in coconut oil is lauric acid, coconut oil may be better choice over partially hydrogenated vegetable oils often containing trans fats. Coconut oil also has powerful health benefits. Lauric Acid, which can help to kill bacteria and other pathogens, but also boost metabolism slightly and increase feelings of fullness compared to other fats. Best choice is virgin coconut oil due to amazing taste and its powerful health benefits.

Butter

Butter contains mainly saturated fat content, for which it has been of the tables for decades. Although it contains Vitamins A, E and K2 and is also rich in the fatty acids Conjugated Linoleic Acid (CLA) and Butyrate, both of which have powerful health benefits. It’s the processed margarine that is a health hazard in many terms, mainly due to the way it has been processed using harmful chemicals and stripped of any beneficial natural nutrients.

Animal Fats ( lard, tallow, bacon)

The fatty acid content of animals tends to vary depending on the diet of animals, so if they diet is predominantly high in grain feeds, it will be high in polyunsaturated fats. Generally animal fats are mainly saturated and have a high smoking point which makes them stable and perfect to use in higher temperatures (frying, braising).

If the animals are pastured raised or grass-fed, there will be more saturated and monounsaturated fats in them. Therefore opting for best quality meat products is the best choice in terms of improving your own health although avoidance of heavy processed meat products is also advised as it can contribute to higher risk of cardiovascular disease.

Unsaturated fats (polyunsaturated and monounsaturated)

Olive Oil

Olive oil is well known for its heart healthy effects and is believed to be a key reason for the health benefits of the mediterranean diet.

It can raise HDL (the good) cholesterol and lower the amount of oxidised LDL cholesterol circulating in your bloodstream.

It is fairly resistant to heating, especially the lighter not extra virgin variety, such as light or pommace olive oil. Extra Virginie olive oil is best used cold, drizzled over salads or added to already prepared meals for extra flavour and nutrition. It's also important to store it in dark cool and dry place to avoid it going rancid and losing nutrients such as powerful antioxidants.

Vegetable and seeds oils

Vegetable oil usually is made of rapeseeds and has euric acid (a toxic, bitter substance) removed from it.
The most of the fatty acids in this oil is monounsaturated, and its often containing Omega-6 and Omega-3 in a perfect 2:1 ratio.
However, rapeseeds needs to go through very harsh processing methods using toxic solvent hexane before it is turned into the cooking oil.
Other vegetable oils are also highly processed, refined products that are way too rich in Omega-6 fatty acids.
These oils have been wrongly considered “heart-healthy” by the media and many nutrition professionals in the past few decades but new research data links these oils with many serious diseases such as cancer and heart disease. Those oils include rapeseed oil, soybean oil, corn oil, sunflower oil.

Nut and peanut oils

Due to a great taste the nut oils have been used in cooking especially in Chinese cooking.
However, they are very rich in polyunsaturated fats, which make them very unhealthy when heated and consumed in excess.They are best used added at the end to ready prepared dishes but should not be reheated or used for frying on high temperatures. The one exception is macadamia nut oil, which is mostly monounsaturated and can be treated same way as olive oil.