Around 250.000 before Christ, was the first time when humans used animal fats to cook. When man learned to produce fire, animal fat was used as edible oil. Today we know, that plants are also a good source of oil. We can distinguish between good fats and bad fats, science has shown that a human body needs fat in a healthy and appropriate amount. But how much fat do we really need? Where do we find it? And how should it be stored ideally?
Unhealthy fats
Trans fat
Trans fat is a byproduct of hydrogenation. This process was used to turn healthy oils into solids to make them durable and prevent them from becoming rancid. High temperatures during cooking can increase the amount of trans fat of oil. Since trans fat has no health benefits, they were banned in many countries, but it still can be found in some margarines, vegetable oils and fried food. The risk of trans fat is high in restaurants, especially if food is fried. Everytime the oil gets reused, the trans fat content increases.
Saturated fat
Products with saturated fat are whole milk, red meat, bacon grease, cheese and coconut oil. A high intake of saturated fat drives up the cholesterol.
Healthy fats
Polyunsaturated fat & monounsaturated fat
Healthy fat can be distinguished from unhealthy fat through consistency. At room temperature, healthy fat is liquid most of the time and not solid. With this in mind, there are two main categories of beneficial fats: Monounsaturated and polyunsaturated fats.

Good sources of monounsaturated fats are olive oil, peanut oil, sunflower oil, canola oil, avocados and most nuts. Polyunsaturated fats are essential fats. They can be broken down in two types of fats: Omega 3 fatty acids and omega 6 fatty acids. Sources of omega 3- fatty acids are fish such as salmon, mackerel and sardines. Other sources of omega 3 fatty acids are flaxseeds, walnuts, soybean oil and canola oil. Sources of omega 6- fatty acids are soybean oil, sunflower oil, walnut oil and corn oils.
The human body cannot produce polyunsaturated fats, but needs them to function. It is used to build cell membranes and to cover nerves. It also is needed for muscle movement and blood clotting. The best way to take in the good fat is with food.
Recommended daily intake of fat
6-20 % of our body weight is fat. According to the American Heart Association, the recommended fat intake for an adult is 30 % of its total caloric intake. A man for example with a calories intake of 2000 per day, has to obtain 600 calories of fat. It can be visible fat like oils or invisible fat like nuts, milk or meat.
How to cook with fats
It is adviced to use saturated fats for frying or cooking at high temperature. They are more stable during cooking and less inflammatory than polyunsaturated oils. Coconut oil and butter and cold pressed sesame oil are a good source of saturated fat. Turns out saturated fat aren’t so unhealthy after all. Olive oil or canola oil are a good choice for low temperature cooking.
How to store oils
In order to overcome oxidation or rancidity, oil shouldn’t be stored in open containers or over-boiled over a period of time. Oils like Flaxseed oil, fish oil, sunflower oil or canola oil are higher in polyunsaturated fatty acids, they undergo rancidity and oxidation faster than coconut oil or palm oil, which have lesser polyunsaturated fatty acids. Rancid oils loose their natural flavour and become unhealthy because they contain free radicals. Free radicals can cause asthma, arthritis, cancer and other chronic diseases.