Essential Fatty Acids
A molecule of any solid fat or liquid is made up of fatty acids. All fatty acids are made up of a carbon chain to which hydrogen is attached. There are three types of fatty acid, saturated, mono- unsaturated and poly-unsaturated.
So called because the carbon atoms in the fatty acid chain carry as many hydrogen atoms as possible and are thus saturated with them. There are long, medium & short chained saturated fats. Saturated fats are stable.
A mono-unsaturated fatty acid has given up two of its hydrogen atoms and created one double bond between two carbons in the chain. Monounsaturated fats are reasonably stable.
A polyunsaturated fatty acid has more than one double bond. These fatty acids are not stable and are easily destroyed by light, air & heat.
Different fats contain these three types in different proportions. The fatty acid composition of wild trout for example is around 26% saturated, 32% monounsaturated & 40% polyunsaturated.
If necessary we can synthesise our own saturated and monounsaturated fats but there are two key polyunsaturated fats; linoleic acid (LA) and alpha linolenic acid (ALA) that can not be made by the body hence they are essential and we must obtain them from the foods we eat.
Essential fatty acids (EFA’s)
LA, known as an omega 3 fatty acid and ALA, known as an omega 6 fatty acid govern so many processes in the body, that without them in the diet, we can expect a myriad of health problems. Essential fatty acids help produce energy from our food and move the energy throughout the body. They govern growth, vitality and mental state. They are involved with the transfer of oxygen from our lungs to our cells and they are part of all cell membranes. They are involved in transmitting messages between cells and they help generate the electrical currents that make the heart beat in an orderly fashion.
To perform many of their functions LA and LNA must first be converted into EFA derivatives.
Each of us is biochemically unique, we differ in our efficiency of converting LA & LNA into EFA derivatives. Some people may lack the ability to make these conversions but more often than not a healthy body can elongate the essential fatty acids into longer chain derivatives. Conversions are, however, greatly hindered by the wrong diet - too little of certain vitamins and minerals (B3, B6, C, magnesium & zinc) and too much saturated fat, altered fats, like hydrogenated fat and trans fatty acids. The longer chained derivatives are especially key in the most active tissues in the body including the brain and sense organs. EPA & DHA are of particular importance and these long chained polyunsaturated fats are found in oily fish. This is one of the reasons it is often recommended to eat oily fish (two times per week in pregnancy), this is especially if you lack the ability to successfully convert the ALA to these longer chained fatty acids. EPA & DHA are also found in algae.
The derivatives important in their own right are also precursors of prostaglandins , short lived hormone like chemicals that influence many body processes but in particular inflammation. Prostaglandins derived from omega 6 derivatives have an inflammatory effect whilst those derived from omega 3 derivatives have an anti inflammatory effect. Studies show that too much omega 6 and not enough omega 3 in the diet creates unwanted inflammation in the body.
Both EFA’s are important in the diet but the prevalence of cheap omega 6 oils and industrially farmed meat & fish have radically affected the balance of these fatty acids in our diets.
The ideal ratio is 3:1. omega 6 to omega 3. Western diets are now so out of balance that the omega 6 to omega 3 balance is often as much as 20:1.
Foods high in omega 3’s
linseed (highest plant based source)
green leafy vegetables
pasture fed eggs
mackerel (highest animal source – but not recommended)
Foods high in omega 6’s
soya bean oil
evening primrose oil
How to balance the essential fatty acids in your diet:
Avoid cooking in soya bean , sunflower, corn & sesame oils, choose butter, coconut oil or 50:50 olive oil/water
Limit processed foods which invariably use the cheaper vegetable oils in their products
Eliminate all processed fats like spreads/margarines
Only use cold pressed vegetable oils
Include the monounsaturated fat omega 9 in your diet – found in olives, hazelnuts, avocado
Eat hemp seeds regularly, add to smoothies, sprinkle on porridge, toss through green leaves. Hemp is one of the very few seeds with an EFA ratio thats right for human nutrition ie 3:1
Add pumpkin seeds and walnuts, which contain both omega 3 & 6, to salads.
Essential fatty acids in pregnancy:
Fetal development, especially visual and neurological, is associated with a higher need for essential fatty acids, and these must come from the maternal diet.
Research shows that increasing maternal intake of essential fatty acids is beneficial to both mother and child - especially during the third trimester and breastfeeding due to the rapid development of the baby’s brain for which fatty acids, especially DHA, are essential.
There is evidence to suggest that low DHA in the mother’s blood is linked to depression during and after pregnancy and consequently some reports show that DHA can increase levels of ‘feel good hormones’.
Signs of essential fatty acid deficiency include; dry scaly skin, decreased growth rate in infants and children, increased susceptibility to infection, and poor wound healing.