Fats are compounds that are required by the body for a number of functions including maintaining cell membrane structure, nerve and brain health, vision, immune function and as a source of energy
Fatty acids are the unit of fats in the body. Fatty acids are joined together in sets of 3 to become triglycerides. These fatty acids (much like amino acids) are classified into essential and non-essential fatty acids.
Fatty Acids are categorised into Polyunsaturated, Monounsaturated and Saturated Fatty Acids. The 2 essential fatty acids (ALA and LA) are both polyunsaturated fatty acids.
These 3 different categories of fats have different functions and effects in the body.
Polyunsaturated fats are considered to be the most beneficial to health. These can be used as fuel and also contribute to many essential functions in the body including regulating inflammation.
Monounsaturated fats are used primarily as a source of energy and do not seem to have any adverse effects.
Saturated fats have been a source of controversy for decades with some considering them as unhealthy, non-essential fats that contribute to diseases like heart disease and diabetes. Others view them as essential to health and not dangerous or disease causing. The medical consensus to date however is that saturated fat (taken in excess of 10% of total daily calories) contributes to the buildup of cholesterol in the blood leading to atherosclerosis (Cardiovascular (CVD) or Heart Disease).
There are 2 essential fatty acids: Omega 3 (ALA – Alpha Linolenic Acid) and Omega 6 (LA – Linoleic Acid).
These essential fatty acids are required by the body as we lack the enzymes to synthesise them. There are many other types of fatty acids – all of which are generally considered to be non-essential as they can be synthesised in the body.
Omega 3 Polyunsaturated Fatty Acid – Alpha Linolenic Acid (ALA) – Daily Requirement – Based on % of Energy Intake: 0.5% calories (kcal). This means if you are an average sized male you need 2500kcal*0.005=12.5kcal energy from ALA. Fat contains 9 kcal per gram. 12.4/9=1.4 grams. Therefore daily requirement for males for ALA (omega 3 fatty acid) is 1.4 grams. One tablespoon of Flax Oil provides over 7 grams of ALA, One tablespoon of Ground Flax Seeds provides 3 grams ALA and 1 tablespoon of Chia Seeds provides about 2.5 grams ALA. So any of these options will guarantee you meet your requirements. However someone who is eating a healthy balanced diet including whole grains, leafy greens, legumes etc. will usually meet the requirement also (how many people do you know have this kind of diet!).
Omega 6 Polyunsaturated Fatty Acid – Linoleic Acid (LA) – Daily Requirement – Based on % of energy intake: 4% calories (kcal). This means if you are an average sized male you need 2500kcal*0.04=100kcal energy from ALA. Fat contains 9 kcal per gram. 100/9=11 grams. Therefore daily requirement for males for LA (omega 6 fatty acid) is 11 grams. LA is found in abundance in sunflower oil (65% LA) and other seed oils. It is also high in Nuts and Seeds. Very few people are at risk of being deficient, unless you go all out Paleo or Carnivore – then you will probably get dry skin (and some other issues!).