Polyunsaturated fatty acids (PUFAs) are found mostly in plant-based foods. PUFAs help your body to maintain the membranes of all cells, and they help it to make prostaglandins, which regulate many body processes, including inflammation and blood clotting. Eating foods rich in PUFAs improves blood cholesterol levels, which can decrease your risk of heart disease. PUFAs may also help decrease the risk of type 2 diabetes. Depending on the location of the double-bond in the fatty acid chain, PUFAs can be classified as omega-3 or omega-6 fatty acids. Most fatty acids are non-essential, meaning that your body can produce them as needed, generally from other fatty acids. However, your body cannot make at least two PUFAs: linoleic acid, an omega-6 fatty acid, and alpha-linolenic acid, an omega-3 fatty acid found in plants. These are essential and you must include them in your diet.
- Omega-6 fatty acids are important for the growth and development of infants, and are a precursor for a hormone-like substance called prostaglandins, which cause constriction or dilation in vascular smooth muscle cells, cause aggregation or disaggregation of platelets, sensitize spinal neurons to pain, induce labor, decrease intraocular pressure, regulate inflammatory mediation, regulate calcium movement, control hormone regulation, control cell growth, act on the thermoregulatory center of the hypothalamus to produce fever, act on mesangial cells in the glomerulus of the kidney to increase the glomerular filtration rate, and act on parietal cells in the stomach wall to inhibit acid secretion.
- Linoleic acid (LA) is the major essential omega-6 fatty acid, and it provides another natural defense against such diseases as cancer, rheumatoid arthritis, eczema, psoriasis, diabetic neuropathy and premenstrual syndrome (PMS). Linoleic acid is found in leafy vegetables, seeds, nuts, and grains, and is especially high in Brazil nuts, pine nuts, sunflower seeds, and pecans.
- Gamma linolenic acid (GLA) is converted by your body from LA. Although most Americans consume large amounts of omega-6 in the form of LA, it may not be converted to GLA because of metabolic problems associated with diabetes, alcohol consumption, trans fatty acids in processed foods, smoking, stress, or illness. For people have trouble converting LA, GLA can be found in rare oils, including black currant, borage, evening primrose, and hemp oils.
- Omega-3 fatty acids are required for normal infant development nervous system maturation, protect against irregular heartbeats and cardiovascular disease, lower triglyceride levels, reduce the risk of heart attack, and reduce the risk of sudden cardiac death in people who already have heart disease. Because omega-3 fatty acids are anti-inflammatory, they help fight and alleviate arthritis, autoimmune disorders, and asthma, and help lower the risk of high blood pressure, coronary artery disease, strokes, and breast, colon and prostate cancers. The omega-3 essential fatty acids are also great for boosting your mood. Low levels of of the omega-3 docosahexaenoic acid (DHA) have been associated with increased risk of suicide.There are three important omega-3 fatty acids, all of which may prevent heart arrhythmias:
- Alpha-linolenic acid (ALA) is a short-chain (18-carbon) omega-3 fatty acid, which is found in many vegetables, beans, nuts, seeds, and fruits. There are relatively large amounts in soy, walnuts, flax seeds, hemp seeds, pumpkin seeds, sesame seeds, mustard seeds, and chia seeds. Brazil nuts and wheat germ also contain significant amounts. It’s also found in green leafy vegetables, grains, and spirulina. Your body cannot make its own ALA, so you need to eat some of these foods each day. Your body can convert ALA to EPA (eiocosapentaenoic acid) and DHA (docosahexaenoic acid).
- Eicosapentaenoic acid (EPA) is a long-chain (20-carbon) omega-3 fatty acid, which is found in very small amounts in microalgae, leafy greens, cruciferous vegetables, and walnuts. EPA lowers your risk of cardiovascular disease. Some EPA is converted into series 3 eicosanoids which can reduce blood clotting, inflammation, blood pressure, and cholesterol. Your body can produce EPA out of ALA and out of DHA.
- Docosahexaenoic acid (DHA) is a long-chain (22-carbon) omega-3 fatty acid, which is found in very small amounts in spirulina, leafy greens, cruciferous vegetables, and walnuts. It is a major component of the gray matter of the brain, and also found in the retina, testes, sperm, and cell membranes. DHA is important for proper nerve and brain development and function. Your body can convert EPA into DHA; however, a high intake of linoleic acid may suppress your body’s ability to convert alpha-linolenic acid to DHA. Avoid refined oils, especially sunflower, safflower, and corn oil, and use tiny amounts of oils containing alpha-linolenic acid such as soy and walnut oils, which will assist your body in making more DHA.
Omega-3 and omega-6 fatty acids are important in the normal functioning of all tissues of the body. Deficiencies can cause many symptoms and disorders including abnormalities in the liver and kidney, changes in the blood, reduced growth rates, decreased immune function, depression, and skin changes, including dryness and scaliness. Adequate intake of the essential fatty acids results in many health benefits, including prevention of atherosclerosis, reduced incidence of heart disease and stroke, and relief from the symptoms associated with ulcerative colitis, menstrual pain, and joint pain.
Your body also makes hormones from essential fatty acids. In general, hormones made from omega-6 fatty acids tend to increase inflammation (an important component of the immune response), blood clotting, and cell proliferation, while those from omega-3 fatty acids decrease those functions. Both types of hormones must be in balance to maintain optimum health.
While most of us don’t typically need supplements or added oils to obtain enough essential fatty acids, we should eat good sources of omega-3 and omega-6 fats daily. An appropriate balance of these essential fatty acids is also important for health. The proper ratio of omega-3 to omega-6 is between 1:1 and 1:4, but Americans tend to have anywhere from 10 to 30 times the amount of omega-6, due to the large amounts of animal products, oils, fast foods, processed foods, and fried foods they eat. Omega-6 fatty acids compete with omega-3 fatty acids in your body, so eating too many omega-6 fatty acids, the result is a silent inflammation that you can’t feel. This chronic inflammation can cause cardiovascular disease, cancer, and inflammatory and autoimmune diseases, including diabetes. To maintain balance, avoid all animal fats, all trans fats, and all refined oils, especially those high in omega-6 such as corn, soy, safflower, sunflower, most vegetable oil blends (typically labeled “vegetable oil”), and sesame oil. Instead, use a tiny amount of low omega-6 oil like olive oil, or saute in a small amount of water or broth. Use applesauce in place of fat in baked treats. Every day, sprinkle some chopped raw English walnuts and raw ground flax seeds on your salad for omega-3 fatty acids.
Your body may not be efficient in converting ALA into DHA and EPA, partly due to genetics or age. Fortunately, consuming sufficient protein, vitamin B6, biotin, calcium, copper, magnesium, and zinc can improve your capacity to convert the parent omega-3 into EPA and DHA. Make whole plant foods, including avocados, soy, nuts, seeds, and olives, the major source of your fat intake. If you use concentrated fats and oils in cooking, favor those rich in monounsaturated fats, such as olive, canola, or nut oils. You can also use oils rich in omega-3 fatty acids, such as flax seed or hemp seed, but never heat them. By all means, avoid processed foods and deep-fat-fried foods rich in trans and omega-6 fatty acids. Don’t let foods rich in saturated fats and cholesterol displace those rich in unsaturated fats, particularly omega-3s. Include an abundance of foods high in omega-3 fatty acids in your diet daily, trying for 2–4 g ALA per day. You can also try adding chlorella, a microalgae high in DHA and EPA, to your diet.
For promoting cardiovascular health, ensuring proper growth and development, or relieving pain, a vegan diet rich in whole fruits, vegetables, nuts, seeds, and legumes will give you the proper ratio of the essential fatty acids.