What are omega 3 fatty acids ?
Omega 3 fatty acids are a group of polyunsaturated fatty acids. There is a fatty acid from this group, alpha-linolenic acid, which falls under the category of essential fatty acids. Other fatty acids such as DHA and EPA in this group can be synthesized by the body. For this to take place to a sufficient extent, it is necessary sufficient plant sources of alpha-linolenic acid to be included in the diet. In omega-3-fatty acids are positive characteristics attributed in the prevention of cardiovascular diseases, arthritis and depression. Omega-3 fatty acids reduce the cholesterol level in the blood, and are, inter alia, of interest to the eye function and the brain metabolism.
Naming
The main omega 3 fatty acids for the (human) body are:
- alpha-linolenic acid (18: 3, n-3, also known by the English abbreviation ALA of α-linolenic acid)
- eicosapentaenoic acid (20: 5 n-3, better known by the abbreviation EPA eicosapentaenoic acid)
- docosahexaenoic acid (22: 6 n-3, better known by the abbreviation DHA docosahexaenoic acid)
Spatial configuration
All the double bonds are in the cis configuration, that is to say that the two hydrogen atoms are on the same side of the double bond, as in almost all natural oils. Spatial having regard to its omega-3 fatty acids is curved, because each cis-double bond causes a bend in the carbon chain. This configuration explains a large number of biological phenomena that are seen in the lipid bilayer of the cell membrane, and other membranes. The fluidity of the cell membrane is determined largely by the content of polyunsaturated fatty acids in the membrane. The functioning of receptors and other membrane proteins, is strongly determined by the fluidity of the cell membrane.
Essential for the human
Strictly speaking, of the omega-3 fatty acids only alpha-linolenic acid is essential. That is to say that this fatty acid, as well as vitamins (except for vitamin D), not made by the human being itself can be received within and to be through the diet. The other omega-3 fatty acids can be made by the body from alpha-linolenic acid. To do this it is necessary that various enzymes in the body are available in sufficient quantities, and that these enzymes are not used for other purposes. Research indicates that the conversion in nearly all people should be both efficient if enough alpha-linolenic acid in the diet is present and the excess of linoleic acid is not too large (± 4 × as much linoleic acid than alpha-linolenic acid).
For people who are in their diet few plant sources of alpha-linolenic acid recording, it is also essential to incorporate some of EPA and DHA in the diet. Except for the making of EPA and DHA has ALA for the body has no function. In women, the transformation (conversion) of ALA to EPA and DHA proceeds easier than men.
Health Effects
Heart and vascular systemThe Inuit (also known as Eskimos) consume large amounts of omega-3 fatty acids from fatty fish. They appear to have an increased HDL-cholesterol levels and a reduced triglyceride levels. There are various scientific investigations that come to the conclusion that fish oil supplements (containing EPA and DHA) decrease the unfavorable LDL-cholesterol and triglyceride levels. Nevertheless, published in March 2006 in the authoritative scientific journal BMJ meta-analysis of studies in the period between 2002 and 2006. In addition, investigators concluded that omega-3 fatty acids have no clear effect on total mortality, cardiovascular diseases and cancer.
This study was more complete than the other, similar studies. The findings were "on the brink" and could hide a potentially significant effect that is not statistically significant.
This conclusion contrasts sharply with another review article from 2006 where Wang et al. 842 articles in the field of primary and secondary prevention have viewed. The conclusion was that increased consumption of omega-3 fatty acids EPA and DHA, from fish and / or food supplements, both overall mortality, the incidence of heart attack and sudden cardiac death decreased. Of interest was, furthermore, that no or only very few complications occurred. A study from the Mayo Clinic confirms the protective effect of omega-3 fatty acid on the heart.
There should be warned of observational studies in this context. In observational studies followed people who may or may not take a particular product. This, however, is very sensitive to selection of health-conscious people. People willing to take a placebo in randomized trials, have a much lower mortality rate than those who do not.
In several epidemiological studies establishing a link between the intake of omega 3 fatty acids and health protective effect. Omega 3 fatty acids work mainly antithrombotic and may reduce the risk of cardiovascular disease, since the following effects have been demonstrated:
- reduction in the fibrinogen levels and improve the flow characteristics of the blood;
- reduction in the levels of blood fats (triglycerides) and thereby a reduction in the risk of "hardening of the arteries" (atherosclerosis);
- formation of vasodilator tissue hormones (eicosanoids);
- increasing the fluidity of cell membranes;
- lowering blood pressure;
- reducing the risk of sudden cardiac death (antiarrhythmic effects);
- improvement of the functioning of white blood cells (leukocytes) in inflammatory responses.
ResolvinesRecently, a new class, by aspirin-triggered, discovered bioactive lipids, which is probably partly responsible for the anti-inflammatory effect of fish oil. Resolvines produced by enzymes from omega 3 fatty acids. The main resolvine is resolvine baptized E1. Human resolvine E1 inhibits the migration of inflammatory cells to the site of inflammation and also prevents other inflammatory cells are activated. Resolvines regulation may explain the recently proved negative side effects of COX-2 inhibitory drugs. This group of drugs is designed to reduce inflammation, but appears to have negative side effects on the cardiovascular system. COX-2 is involved in the production of resolvine E1 and inhibition of this COX-2 enzyme is also possible to block the production of resolvine E1, which makes an important group of anti-inflammatory substances is inhibited.
Brain functionsThe nervous system has all of the tissues in the body fat percentage highest. According to Dr. David Horrobin, a pioneer in research on essential fatty acids, approximately 8% of the brains of omega 3 fatty acids. DHA, in particular, there is incorporated into phospholipid membranes, and in the myelin sheath surrounding nerve cells. For this reason, omega-3 fatty acids used in a variety of mental disorders:
Aggression
Not only mice but also people seem prone to omega-3 fatty acid intake associated with aggression. It turns out that murder is more common in people who eat enough omega-3 fatty acids. Low blood levels of these fatty acids are often seen in people who have been thrown on the bill for public violence. Through years of intake of omega-3 fatty acids, however, takes off aggression. Two studies have shown a positive effect of omega 3 fatty acids on impulse control / aggression.
Clinical depression
The omega-3 fatty committee of the American Psychiatric Association (APA), the studies analyzed the potential beneficial effects of omega-3 fatty acids and comes to the conclusion that they have a beneficial effect on depression.
Bipolar disorder
A study by Andrew L. Stoll and colleagues at Harvard University, is one of the first systematic attempts to clinically demonstrate the link between omega-3 fatty acids and improve the momentum transfer in the brains. They found that patients with bipolar disorder (sometimes called manic-depressive illness), after nine months of fish oil supplementation were significantly refurbished in comparison to a placebo group. Currently, much research has been carried out into the effect of omega 3 fatty acids on the momentum transfer in nerve tissue and its clinical effect. In the meantime, it has been shown that omega-3 fatty acids to make a positive contribution to the treatment of bipolar disorder.
Schizophrenia
Epidemiological research has shown a link between low intakes of omega 3 fatty acids and the occurrence of psychoses. In clinical trials prove omega-3 fatty acids have a positive effect on the treatment of schizophrenia and the occurrence thereof. It appears in youth work as well as the current available neuroleptics (atypical antipsychotics).
ADHD
Children in their early years have shortages of omega-3 fatty acids have later been ADHD or take a more aggressive stance, it is argued by some scientists. Studies on the effect of omega 3 fatty acids on ADHD have partly seen contradictory effects. Sometimes with positive effects as a result, while found no beneficial effects in other studies. The quality of certain studies is not always good.
Animal tests show that brain function and blood flow are favorably influenced by the administration of omega-3 fatty acids. In theory, omega-3 fatty acids would reduce the risk of developing Alzheimer's disease. However, this is not apparent from examination: the results of studies are sometimes contradictory, or the quality of the studies is insufficient.
Recommendations of the omega-3 fatty acid Commission of the APA for the use of omega-3 fatty acids in psychiatry:
- All adults should eat fish at least twice a week
- Patients with mood, impulse Management and Control, or psychotic disorder, should consume 1 gram of EPA + DHA
- A supplement may be useful in patients with a mood disorder (1-9 g per day). Use of 3 g per day under the supervision of a physician.
Eye functionOmega 3 fatty acids can contribute to the prevention of macular degeneration (MD). However, the studies accompanied sometimes contradictory, and are not always of equal quality. A recommendation, on the use of omega-3 fatty acids for the prevention of MD, one can, therefore, do not as yet.
The sight of infants improved by supplementation with omega-3 fatty acids. For safety reasons, no use advice can be given because of the role of omega-3 fatty acids in the development of the immune and vascular system of the newborns. Larger studies are needed to better highlight its safety and effectiveness.
Autoimmune diseasesBecause of its anti-inflammatory properties of omega-3 fatty acids, these fatty acids are also examined in the context of inflammatory diseases and autoimmune diseases (such as Crohn's disease and rheumatoid arthritis). The beneficial effects of omega-3 fatty acids in rheumatoid arthritis have been demonstrated. Anti-inflammatory effects of fish oil were seen at doses between 2.6 to 7.1 grams of omega-3 fatty acids (EPA + DHA) per day. A dosage of 1 gram per day of omega 3 is ineffective.
Ratio of omega 6 / omega 3
In recent decades, the diet changed in the industrialized world. As a result, one gets a lot of saturated fat inside, and relatively few of the healthier polyunsaturated fatty acids.
Clinical studies indicate that a proper ratio between omega 6 and omega 3 fatty acids in the diet is important for the health of the cardiovascular system.
Omega 3 and Omega 6 are converted using the same enzyme system, so the omega 6: omega 3 ratio has an important influence on the produced eicosanoids (e.g., prostaglandins, leukotrienes, thromboxanes, etc.) out of these fatty acids, and in this way also the metabolic functions of the body. Metabolites of omega-6 fatty acids are significantly more pro-inflammatory than that of omega-3 fatty acids. This means that omega 6 and omega 3 fatty acids should be consumed in a balanced proportion. Researchers assume that the ideal ratio between 3: 1 and 5: 1. Research seems to indicate that the prehistoric man diet, rich in seafood, nuts and other omega-3 sources has provided such a relationship. A typical Western diet has an omega 6: omega-3 ratio of between 10: 1 to 30: 1, so dramatically out of balance in the direction of omega-6 fatty acids. Most vegetable oils contain relatively much more omega 6 than omega-3 fatty acids. Examples include soybean oil, sunflower oil, safflower oil, cotton seed oil, peanut oil and corn oil.
Known or suspected risks of omega 3 fatty acids
Affect blood clotting
At dosages of more than 3 grams of fish oil per day, the blood coagulation can be inhibited, making it easier for bleeding may occur.
Reduced glycemic control in diabetics
In diabetic patients would be high doses of fish oil may lead to a reduction of the glycemic control, however, this is controversial.
A reduction in immune and inflammatory responses
Suppression of immune and inflammatory responses, resulting in a decreased resistance to infections and increased susceptibility to opportunistic infections.
Warning for people with heart failure
In heart failure, cells fed enough blood just barely get ornery. This can then lead to an increased risk of cardiac arrhythmia, which can lead to sudden cardiac death. Omega-3 fatty acids stabilize the heart rhythm by setting this on sensitive cells out of action, which reduces the risk of cardiac arrhythmias and sudden cardiac death. In people with heart failure, the heart pumps already barely enough blood around to keep them alive, so the failure of the sensitive cells can lead to the heart no longer able sufficiently pump blood, which increases the risk of death.
An increase in the risk of prostate cancer
Scientific research shows a connection between show high concentrations of omega-3 fatty acids in the blood and an increased risk of developing prostate cancer.
Sources of Omega-3 fatty acids
- Fatty cold-water marine fish
In many Southern European countries make fish an important part of the food pattern, however, in the Netherlands and Flanders is the group of people who regularly eat oily fish small.
Although fish is a major source of omega 3 fatty acids, these fatty acids make fish to yourself. They obtain them from the algae they consume. For this reason, there is often a significant difference in DHA and EPA concentrations between farmed versus caught fish.
On consumption of these fatty fish must moreover be alert to the possible presence of heavy metals and fat-soluble toxins such as PCBs and dioxins, which may accumulate in the food chain.
- Vegetable oils
- Flaxseed oil (57%)
- Chiazaadolie (Salvia hispanica) (55%)
- Sacha-inchi-oil (48%)
- Hemp oil (20%)
- Walnut oil (approximately 10%)
In theory the body from alpha-linolenic acid can synthesize EPA and DHA. the delta-6 desaturase-enzyme works in most people sufficiently efficient if sufficient Alpha-linolenic acid is provided in the diet.
- Dietary Supplements
Fish oil supplements
Most manufacturers of fish oil supplements remove heavy metals and other contaminants from the oil, in various ways, so that the purity and safety is greatly improved. One of the best methods to get rid of contaminants fish oil is molecular distillation. Fish oils which have been subjected to molecular distillation contain no measurable levels of contaminants more.
Not too much Cod
Cod liver oil should not be considered as a sufficient source of omega-3 fatty acids. Admittedly, there are also omega-3 fatty acids, but to avoid the potentially toxic overdose of vitamins A and D (where cod liver oil is rich) is not recommended cod liver oil (fish liver oil) as sole source of omega 3 fatty acids.
Krill oil
Krill, a small shrimp-like plankton animal is a lesser known source of omega 3. The oil is extracted using a patented process.
EPA / DHA from algae
The microalgae Crypthecodinium cohnii and Schizochytrium are rich sources of DHA, and are commercially produced in bioreactors. Oil from brown algae (kelp) is a source of EPA. A new type of algae with both EPA and DHA has been recently discovered and is grown commercially. Algae contain EPA and DHA in the form of phospholipids, in contrast to triglycerides in fish oil.