Essential Fatty Acids
How the Brain & Body Talk
to Themselves and Each Other
Essential Fatty Acids (EFAs) are raw materials from which the body makes hormones and some neurotransmitters . . . a wide variety of vital substances that allow cells to communicate with each other. EFAs also make eicosanoids - chemicals that communicate within the cell itself.
If B vitamins are like the body's spark plugs and trace minerals like the nuts and bolts that hold everything together, essential fatty acids are like the car's electrical system . . . sending and receiving critical signals that control everything that goes on and powering all the little accessory electrical devices. EFAs are essential nutrients - the body can't do without them and can't make them itself, so it needs to get them from food.
This article summarizes the peer-reviewed evidence base on the effects EFAs have on mental health. For guidance in how to use EFAs, click here.
EFAs are also critical building blocks for the physical structure of the brain itself - neuronal cell membranes have large EFA components. EFAs are critical parts of the microstructures in cell walls that allow some molecules in while keeping others out, so they're critical to maintaining the balance of nutrients that cells need to do their jobs. The cellular electrical potentials they maintain help cells communicate with each other electrically (especially important in the nervous system.) EFAs attract oxygen and are therefore important in many cellular processes such as oxygen transport through our lung tissue into the blood and through the walls of our red blood cells into their cytoplasm, the fluid inside the red blood cell. EFAs also help produce hemoglobin itself.
EFAs repel each other weakly, meaning they don't clump together. This property helps cell membranes maintain their fluid, adaptable nature. This property also makes the EFAs a little like soap - the structures they create have the ability to transport toxins toward the surface of the organs they are a part of, whether it's the skin, the intestines, the kidneys or the lungs.1 This helps the body detoxify itself.
EFAs are very fragile molecules. They oxidize and are destroyed when exposed to heat, light or air.2 This can make it next to impossible to get adequate amounts of these critical nutrients from diets rich in processed food, or even diets of less-processed but largely cooked food. A number of researchers have found strong relationships between diets deficient in EFAs and emotional disorders ranging from an increased susceptibility to stress to criminal behavior.3
There are several families of EFAs, distinguished by their chemical structure and also by their actions in the body. They're called w3s (aka: omega 3s, sometimes abbreviated as n3s or w3s in the medical literature) w6s (omega 6s) and w9s (omega 9s.)
W3s are the most chemically reactive. This makes them very useful biologically but also makes the fragile: they oxidize (go rancid and spoil) quickly when exposed to light, air or heat. Because of this w3s are often removed from food products to keep them from going bad. This is why it's hard to get enough w3s from food. This is sad - the w3s are critical. Among other things, adequate w3s can tell tumor cells to kill themselves, protecting us from cancer.4
W6s are also important. Like w3s they're a critical part of cell membranes and also serve as raw materials for many important substances cells and tissues need to communicate with each other. Like w3s they're fragile molecules but the w3s are much more fragile: w6s oxidize (go rancid) only 1/5 as quickly as the w3s. So w6s are easier to get from food than w3s are.
W3s and w6s have opposite effects in some areas. For example, the w6s produce natural body chemicals ("bad" prostaglandins) that create inflammation (inflammation does have its purposes at times.) W3s produce chemicals that reduce inflammation ("good" prostaglandins.) These often-opposing effects, coupled with the relative lack of the easily-spoiled EFAs in a modern diet of processed, cooked food, means that the balance of w3s and w6s we eat is critical to good overall health, and especially mental and emotional health.
In the human diet, we get only a small fraction of the w3s that we probably need.5 We tend to get far more w6s than we should; this can create an overactive immune system and inappropriate inflammatory responses.6 Adding w-3s to the diet reduces this inappropriate immune-mediated inflammation.7 A consensus has emerged that the best approach is to try to consume twice as many w3s as w6s, even though healthy bodies contain more w6s than w3s. There's roughly 4-5 times as many w6s in the body than w3s, however in the brain the ratio evens out and the optimal ratio in the brain seems to be an even: 1:1.8
Researchers have shown a relationship between low levels of w3s and depression,9 as well as a higher severity of depression when the w3/w6 ratio is low (more w6s and less w3s.) It appears that an elevation in w6s, typical of modern diets, is associated with an increase in pro-inflammatory neurotransmitters. When brain tissue is inflammed, even mildly, substantial changes happen in brain cell membranes that alter their ability to receive signals from other neurons; it's thought that this may be be the mechanism leading to the observed changes in mood. Diets high in w3s have the opposite effect: calming inflammation and helping restore optimal communication between neurons.
Adding w3s to the diet of depressed people can improve their moods.10 It appears that this effect may be due, at least in part, to changes in the sodium/potassium pump that occur in response to changing w3/w6 ratios in cell membranes.11 At least one study has even reported a relationship between levels of w3s in fat tissue not in the brain and depression!12
Essential fatty acids also help moderate the effect of physical and psychological stress, lowering the release of glucocorticoids under stressful conditions.13 EFAs can moderate the adverse effect allergic inflammation has on the brain's ability to learn, probably by increasing the ability of neurons to communicate with each other.14 EFAs also protect the brain's ability to learn from neurotoxins that interfere with the monoamine neurotransmitters (dopamine, adrenaline, noradrenaline) as well as serotonin.15
As mentioned above, it's generally thought that the ideal ratio for a dietary supplement is roughly two times as many w3s as w6s and w9s together. A good essential fatty acid supplement needs to be made in just the right way (one detail of many: copper fittings in the oil presses or bottling equipment will start the oxidation process and spoil the oil. ) My personal favorite is Flora's Udo's Choice, although some knowledgeable people swear by Barlean's products. The best oils should be refrigerated at the store and at home.
Good fish oils also supply w3s, w6s and w9s, and virgin olive oil can be a useful source of some EFAs as well.
Whatever your source, it's important to bear in mind that these critical nutrients spoil easily so it's important to pay for good quality. Take 1-2 tbsp/day for maintenance; 2-4 tbsps a day will not only maintain optimal functioning throughout the brain and the rest of the body but also frequently help people lose weight.
And of course, it's important to supply your body with adequate B vitamins, fully-chelated trace minerals and antioxidants so that it will have all necessary co-factors for utilizing your EFA oils.
1. Erasmus, Udo. 1993. Fats that Kill, Fats that Heal. Burnaby, B.C., Canada: Alive Books. 45. Much of the material in this section is adapted from this book.
2. Ibid. 6.
3. Ibid. 356-7, also check out the individual researchers cited on these pages.
4. Leaver, H.A. et al. 2002. Antitumor and pro-apoptotic actions of highly unsaturated fatty acids in glioma. Prostaglandins, Leukotrienes, and Essential Fatty Acids. 66(1):19-29.
5. Spector, A.A. 2001. Plasma free fatty acid and lipoproteins as sources of polyunsaturated fatty acid for the brain. Journal of Molecular Neuroscience.16(2-3):159-165.
6. Calder, P.C., Grimble, R.F. 2002. Polyunsaturated fatty acids, inflammation and immunity. European Journal of Clinical Nutrition. 56 Suppl. 3:S14-19.
7. Calder, P.C. 1997. N-3 polyunsaturated fatty acids and cytokine production in health and disease. Annals of Nutrition and Metabolism. 41(4):203-234.
8. Erasmus. Ibid. 53.
9. Brunner, J. et al. 2002. Cholesterol, essential fatty acids, and suicide. Pharmacopsychiatry. 35(1):1-5.
10. Colin, A. et al. 2003. Lipids, depression and suicide. Encephale. 29(1):49-58.
11. Djemli-Shipkolye, A. et al. 2003. Differential effect of w3 PUFA supplementations on NA, K-ATPase and Mg-ATPase activities: possible role of the membraine w6/w3 ratio. The Journal of Membrane Biology. 191(1):37-47.
12. Mamalakis, G. et al. 2002. Depression and adipose essential polyunsaturated fatty acids. Prostaglandins, Leukotrienes and Essential Fatty Acids. 67(5):311-318.
13. Yehuda, S. et al. 2000. Fatty acid mixture counters stress changes in cortisol, cholesterol, and impair(ed) learning. International Journal of Neuroscience. 101)1-4:73-87
14. Yehuda, S. et al. 1997. Essential fatty acid preparation improves biochemical and cognitive functions in experimental allergic encephalomyelitis rats. European Journal of Pharmacology. 328(1):23-29.
15. Yehuda, S. et al. 1995. Essential fatty acid preparation (SR-3) rehabilitates learning deficits induced by AF64A and 5,7-DHT. Neuroreport. 6(3);511-515.