Omega 3 Fatty Acids

Omega-3 fatty acids are considered essential fatty acids: They are necessary for human health but the body can' t make them -- you have to get them through food. Omega-3 fatty acids can be found in fish, such as salmon, tuna, and halibut, other seafood including algae and krill, some plants, and nut oils. Also known as polyunsaturated fatty acids (PUFAs), omega-3 fatty acids play a crucial role in brain function as well as normal growth and development. They have also become popular because they may reduce the risk of heart disease. 

Omega-3s are termed essential fatty acids (EFAs) because they are critical for good health. Since the body cannot make them on its own, omega-3s must be obtained from food.

Functions of Omega fatty Acids

Ø  Reduce hypertension:  Several clinical studies suggest that diets or fish oil supplements rich in omega-3 fatty acids lower blood pressure in people with hypertension. Studies of large groups of people have found that the consumption of omega-3 fatty acids may aid in lowering overall blood pressure level.

Ø  Improve heart health: One of the best ways to help prevent heart disease is to eat a diet low in saturated fat and to eat foods that are rich in monounsaturated and polyunsaturated fats (including omega-3 fatty acids). Clinical evidence suggests that EPA and DHA (eicosapentaenoic acid and docosahexanoic acid, the two omega-3 fatty acids found in fish oil) help reduce risk factors for heart disease, including high cholesterol and high blood pressure. Fish oil has been shown to lower levels of triglycerides (fats in the blood), and to lower risk of death, heart attack, stroke, and abnormal heart rhythms in people who have already had a heart attack. Omega-3 fatty acids may play a part in keeping cholesterol levels low, stabilizing irregular heartbeat (arrhythmia), and reducing blood pressure.

Ø  Protecting the heart:  Researchers now believe that alpha-linolenic acid (ALA), one of the omega-3s, may be particularly beneficial in protecting against heart and blood vessel disease, and for lowering cholesterol and triglyceride levels.

Ø  Diabetes:  often have high triglyceride and low HDL levels. Omega-3 fatty acids from fish oil can help lower triglycerides and apoproteins (markers of diabetes), and raise HDL, so eating foods or taking fish oil supplements may help people with diabetes. Another type of omega-3 fatty acid, ALA (from flaxseed, for example) may not have the same benefit as fish oil. Some people with diabetes can' t efficiently convert LNA to a form of omega-3 fatty acids that the body can use.

Ø  Rheumatoid arthritis:  Most clinical studies examining omega-3 fatty acid supplements for arthritis have focused on rheumatoid arthritis (RA), an autoimmune disease that causes inflammation in the joints. A number of small studies have found that fish oil helps reduce symptoms of RA, including joint pain and morning stiffness. One study suggests that people with RA who take fish oil may be able to lower their dose of non-steroidal anti-inflammatory drugs (NSAIDs). However, unlike prescription medications, fish oil does not appear to slow progression of RA, only to treat the symptoms. Joint damage still occurs.

Ø  Osteoporosis:  Some studies suggest that omega-3 fatty acids may help increase levels of calcium in the body and improve bone strength, although not all results were positive. Some studies also suggest that people who don' t get enough of some essential fatty acids (particularly EPA and gamma-linolenic acid [GLA], an omega-6 fatty acid) are more likely to have bone loss than those with normal levels of these fatty acids. In a study of women over 65 with osteoporosis, those who took EPA and GLA supplements had less bone loss over 3 years than those who took placebo. Many of these women also experienced an increase in bone density.

Ø  Depression: Studies have found mixed results as to whether taking omega-3 fatty acids can help depression symptoms. Several studies have found that people who took omega-3 fatty acids in addition to prescription antidepressants had a greater improvement in symptoms than those who took antidepressants alone. However, other studies have found no benefit. Studies are also mixed on whether omega-3 fatty acids alone have any effect on depression. Depression is a serious illness and you should not try to treat it on your own. See a doctor for help.

Ø  Skin disorders: In one clinical study, 13 people with sun sensitivity known as photo dermatitis showed less sensitivity to UV rays after taking fish oil supplements. However, topical sunscreens are much better at protecting the skin from damaging effects of the sun than omega-3 fatty acids. In another study of 40 people with psoriasis, those who took EPA with their prescription medications did better than those treated with the medications alone. However, a larger study of people with psoriasis found no benefit from fish oil.

Ø  Asthma: Studies examining omega-3 fatty acids for asthma are mixed. In one small, well-designed clinical study of 29 children with asthma, those who took fish oil supplements rich in EPA and DHA for 10 months reduced their symptoms compared to children who took placebo. However, most studies have shown no effect.

Ø  Colon cancer: Eating foods rich in omega-3 fatty acids seems to reduce the risk of colorectal cancer. For example, Eskimos, who tend to have a high-fat diet but eat significant amounts of fish rich in omega-3 fatty acids, have a low rate of colorectal cancer. Animal studies and laboratory studies have found that omega-3 fatty acids prevent worsening of colon cancer. Preliminary studies suggest that taking fish oil daily may help slow the progression of colon cancer in people with early stages of the disease. If you have colorectal cancer, ask your doctor before taking any supplements.

Ø  Breast cancer: Although not all experts agree, women who eat foods rich in omega-3 fatty acids over many years may be less likely to develop breast cancer. More research is needed to understand the effect that omega-3 fatty acids may have on the prevention of breast cancer.

Ø  Prostate cancer: Population based studies of groups of men suggest that a low-fat diet including omega-3 fatty acids from fish or fish oil help prevent the development of prostate cancer.

Food Sources of Omega-3

Key omega-3 fatty acids include eicosapentaenoic acid (EPA), docosahexanoic acid (DHA), and alpha-lineolenic acid (ALA). EPAs and DHAs are found in oily cold-water fish such as tuna, salmon, and mackerel, as well as fresh seaweed. ALAs are found primarily in dark green leafy vegetables, flaxseed oils, and certain vegetable oils.

Omega-3 fatty acids are very safe to consume. However, most experts recommend limiting fish consumption to two to three servings weekly because so many fish may be tainted with mercury and other contaminants. Fish oil capsules do not usually present this same risk.

Deficiency and Disease of Omega 3

There are no known side effects associated with increasing your intake of omega-3 fatty acids through foods, although fish oil capsules do pose the risk of a "burp" factor – a harmless, sometimes unpleasant.