• Women who consumed a minimum of five servings of fish per week over a 16‐year period lowered their risk of coronary heart disease (CHD) by more than a third, and reduced their risk of fatal heart attack by half. - April 10, 2002 issue of JAMA
• Men without heart disease were 81% less likely to experience sudden death due to fatal arrhythmia (irregular heartbeat) when their blood levels of omega‐3 fatty acids were high regardless of their age, smoking habits or amount of other types of fatty acids in their blood. - April 11, 2002 New England Journal of Medicine
• Patients who ate fish and had high serum levels of alpha linolenic acid (ALA), (EPA), and (DHA) reduced their risk of all‐cause mortality in direct relation to the amounts consumed. Patients who consumed the most omega‐3 had a 55% lower risk of death from cardiovascular disease, heart attack, and stroke, and a 51% lower risk of death from coronary artery disease. - American Journal of Clinical Nutrition (July 2003).
Scientific Research on Omega-3 Essential Fatty Acids
Omega-3 essential fatty acids are a form of polyunsaturated fats. These are one of four basic types of fat that the body derives from food. (Cholesterol, saturated fat and monounsaturated fat are the others). Consumption of high amounts of food rich in saturated fats has been associated with degenerative diseases such as heart disease and even cancer.
However, consumption of polyunsaturated fatty acids such as omega-3s is actually good for you. Omega-3 essential fatty acids are reported to be beneficial in controlling many metabolic disorders such as cardiovascular diseases, osteoporosis, psychological disorders, inflammatory conditions (including arthritis), skin disorders and non-insulin-dependent (or type II) diabetes.
Omega-3s are considered “essential” fatty acids because they are essential to human health but cannot be manufactured by the body. They must be obtained through the diet or supplementation. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are two important omega-3 fatty acids. Both EPA and DHA are found primarily in cold-water fish.
Omega-3 essential fatty acids may be helpful for a variety of health concerns. Its best-documented benefits are for heart disease and problems that contribute to heart disease.3 The body uses Omega-3s as one of the primary structural components to form membranes surrounding our cells.1, 2 Without a sufficient supply of polyunsaturated omega-3s, the body will use saturated fat to construct cell membranes.
This results in cell membranes and blood vessels that are less elastic, which has a negative effect on the cardiovascular system. Studies suggest that EPA and DHA found in fish oil aid in reducing risk factors for heart disease, including high blood pressure and high cholesterol.
Studies have shown that the more omega-3 fatty acids people consume, the lower their overall blood pressure is.4, 5 Those who live in areas of the world where consumption of omega-3s from fish is higher tend to have higher levels of HDL (or good) cholesterol levels and decreased levels of triglycerides (fatty material that circulates in the blood).6, 7, 8
Supplements containing EPA and DHA have been shown to reduce LDL (or bad) cholesterol and triglycerides. Strong evidence also suggests that these substances can help prevent and treat atherosclerosis by inhibiting the development of arterial plaque and blood clots, which both tend to clog arteries.9, 10
Omega-3 fatty acids have the ability to decrease the stickiness of blood cells (called platelet aggregation).11 This reduces such complications as blood clots and stroke. DHA and EPA also act as antioxidants.12 These effects prevent damage to the heart and reduce the risk of heart diseases.
Omega-3 fatty acids may decrease inflammation and reduce pain associated with rheumatoid arthritis.13 EPA and DHA are successful at keeping the body free from inflammation because they can be converted into natural anti-inflammatory substances called prostaglandins and leukotrienes, compounds that help
decrease inflammation and pain.14, 15
While most research has focused on the positive effects of Omega-3 essential fatty acids on rheumatoid arthritis, they may also be helpful for osteoarthritis and other joint conditions. In some laboratory studies, omega-3 fatty acids decreased inflammation and reduced the activity of enzymes that destroy cartilage.16,17
Diabetics may benefit from taking supplements that contain EPA and DHA. Low HDL and high triglyceride levels tend to be associated with people who have type II diabetes. Omega-3 fatty acids from fish oils have been shown to help raise HDL (good cholesterol) and lower triglycerides (fatty material in the blood). 18,19
Studies suggest that people who are lacking in certain essential fatty acids (like EPA) are more likely to suffer from bone loss than those with normal levels of these fatty acids. Omega-3s such as EPA help increase calcium absorption in the body, in part by enhancing the effects of vitamin D, reducing urinary excretion of calcium and increasing calcium deposition in bone. All of these improve bone strength and enhance the synthesis of bone collagen. These effects from essential fatty acids will benefit menopausal women, who are prone to bone loss, and reduce the risk of osteoporosis.
Supplementation with calcium and omega-3 essential fatty acids has been shown to be effective in reducing and preventing osteoporosis in the elderly.20
Essential fatty acid metabolism seems to play a crucial role both in the pathogenesis and treatment of skin conditions such as psoriasis.21 One study showed that people treated with medications and omega-3 fatty acids for psoriasis did better than those treated with medications alone.22 Another study administered
over a 12-month period indicated that that EPA could be beneficial for the long-term treatment of psoriasis.23
Eye and Nervous System Health
DHA plays a critical role in the development of the visual and central nervous system.24 Increased intake of
omega-3 fatty acids has been associated with a decreased risk of developing macular degeneration,25 which is a leading cause of vision loss in the elderly. Lower levels of brain DHA is associated with cognitive impairment.26
In 2001, the FDA allowed DHA to be added to infant formula. Not only does DHA help infant brain development, it may also prevent post-partum depression in nursing mothers.27 Human adults maintain a constant level of DHA in brain tissue. Supplementation of DHA may be helpful in the prevention of psychological disorders such as depression, schizophrenia and Alzheimer’s disease.28,29 Scientific studies
have found that low levels of omega-3 fatty acids in the blood are associated with depression.30
While DHA plays an important role in the development of the nervous system, it also protects nervous tissues31 and may be of benefit in preventing nerve damage.32
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