Omega 3 Fatty Acids
Definition of Omega 3 Fatty Acid
Omega 3 fatty acids are natural fats that confer many health benefits. You will see them in the vitamin and supplement aisles when you shop, but you may not know what they are, where they come from, and why they are good for you.
Fatty acid is another word for fat. The fat in butter, lard, and other meat-derived fat is called saturated fat, and it is bad for your cardiovascular system and health. Polyunsaturated fatty acids (PUFAs) can be good for you, and they are found in vegetables and fish. There are two main kinds of PUFAs needed in your diet, Omega 3 fatty acids and omega-6 fatty acids.
Two specific PUFAs are essential, because the body cannot make them and cannot function without them. They are linoleic acid (LA), omega-6 fatty acid, and α-linolenic acid (ALA),an Omega 3 fatty acids.
Omega-6 fatty acids are a part of many people’s normal diets. They can be found in soybeans and oil, sunflower, safflower, and corn oils. Most people get enough LA and omega-6 fatty acids.
One the other hand, omega-3 fatty acids, which come mainly from fish, are frequently lacking in the diet.
The Omega 3 fatty acids include alpha linolenic acid (ALA) which is essential, and docosahexanoic acid (DHA) and eicosapentenoic acid (EPA) which can be made in the body, but in small amounts. They have slightly different pathways and functions in the body.
ALA seems to be less critical, except for its conversion in small amounts to EPA and DHA. EPA may be more important for heart health, while DHA may be more critical to brain function, although both EPA and DHA contribute to good health. DHA is present in the retina and critical to its function.
Benefits of Omega 3 Fatty Acids
These substances are very active in the human body. They help make up parts of cell walls, including those in the brain and nervous system. DHA is very active in the brain, being involved in cell-to-cell signal transmission, as well as being made into other compounds that reduce brain inflammation when there is a lack of blood flow.
ALA is metabolized via a number of steps into a group of biologically active chemicals that are related to inflammation in the body. EPA is metabolized into a similar group of chemicals. The chemicals derived from EPA can actually protect the heart and other organs from injury.
EPA inhibits the clumping of platelets which cause clots, as well as preventing blood vessels from further constricting when injured at the microscopic level from things like cholesterol. At the same time, substances derived from EPA help open up the flow in blood vessels.
These omega-3 fatty acids are being studied all over the world by doctors in every specialty, because they are so important to health. They make up a part of the body’s ability to help prevent and/or limit the damage from heart attacks and strokes. They are undoubtedly key to many normal and many abnormal reactions in the body, which must be understood.
The American Heart Association recommends 500 mg a day of EPA and DHA, on average, to prevent heart problems. This can be accomplished by eating 2 meals a week of fatty fish, or by taking supplements.
For prevention of another event after a first heart attack, the AHA recommends more - 1 gram a day of EPA/DHA. This will probably mean taking a supplement for most people.There are even higher doses recommended for certain conditions in which there is an excess of undesirable fats in the blood. There is even a prescription form of EPA/DHA.
Omega 3 rich foods and Omega 3 supplements
ALA can be found in green leafy vegetables, as well as vegetable oil. Walnuts and soy, canola and flaxseed oil are all rich in ALA. Flaxseed oil must be kept in a dark, cool area since it easily goes rancid. Vegetarians must get their EPA and DHA from the conversion of ALA, so they need a way to find a lot of it, which is difficult with their dietary limitations.
EPA and DHA are found in fatty fish, fish eggs, and fish oil. Organ meats from animals also contain EPA and DHA. The fatty fish richest in omega-3s include salmon, herring, tuna, halibut and mackerel from the ocean. Good freshwater fish are lake herring, lake trout, whitefish and freshwater trout.
The main omega-3 fatty acids found in fish is EPA. The DHA in fish and fish oil comes from fermented microalgae eaten by the fish. Fermented microalgae are an excellent source of DHA and the source of this fatty acid when it is added to infant formula in the United States. Vegetarians can use this source if it they can find it.
ISSFAL (The International Society for the Study of Fatty Acids and Lipids) states that the conversion of ALA to DHA is 1% in infants and less in adults. This means that babies may not get enough and that vegetarians who will not take supplements can have deficiency of DHA.
Most groups recommend between 250 mg and 500 mg of EPA and DHA a day for healthy people. This means taking supplements for most people, who do not eat enough fish.
Pregnant women are advised to take EPA and DHA. These fatty acids do get into breast milk. Infant formula can also contain EPA and DHA. While studies to date have not found any definite relationship between omega-3 intake and any specific abnormalities in children, they are suggested for pregnant women and young children to help support normal growth and development.
There is no known disease caused by a lack of omega-3 fatty acids. The protective effects of these substances are just not available for people who don’t take in enough of them. While ALA is an essential fatty acid, most people seem to get enough of it.
Lack of these fatty acids has been studied and will continued to be studied, as will the use of them to help prevent or improve everything from heart disease to Alzheimer’s disease.
Side Effects of Omega 3 and Safety
Omega-3 fatty acids are very safe. At lower doses almost no problems are reported. At higher doses there can be an increase in flatulence or gas, some dyspepsia, and belching, including belching with a fishy flavor.
The worst things reported with very high doses is dyspepsia (indigestion), some flu-like symptoms and mild elevations of liver function tests which become normal when the dose is dropped. They only concern is the level of mercury in some fish. You must know where your fish is coming from and how safe it is, or you should take supplements.
Visual benefits of Omega 3 Fatty Acids
Multiple studies have shown an association between high intake of omega-3 fatty acids (especially DHA) and lower risk of age-related macular degeneration. The fact that omega 3 fatty acids protect blood vessels would seem to be important in regards to retinal diseases that involve the blood vessels.
Most of the studies have focused on Age-Related Macular Degeneration but these fatty acids could help treat or stabilize diabetic retinopathy and other conditions in which retinal blood vessels are damaged and abnormal. These connections are all being studied in older individuals.
Children are not at risk for age-related macular degeneration or the kind of cardiovascular disease that happens to older adults. Children should take vitamins suggested by their doctors that take all their health needs into account. Read more about , Omega 3 Benefits for the eye.
Results of the AREDS2 study, which includes omega-3 fatty acids, will start to be available toward the end of 2012. AREDS and AREDS2 have both tried to find supplements and vitamins that can help prevent age-related macular degeneration, or keep it from progressing. Other effects on the eyes are also being studied. Read more about AREDS 2
For now, follow your general doctor’s advice on Omega 3 fatty acids intake for heart and other vascular health. You should also ask your eye care professional if you should be taking the AREDS or AREDS2 formula now or any parts of it. Most people will probably benefit from increasing their intake of Omega 3 fatty acids.