Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history.
Seafoods can be prepared in a variety of ways. It can be uncooked (raw) (cf. sashimi). It can be cured by marinating (cf. escabeche), pickling (cf. pickled herring), or smoking (cf. smoked salmon). Or it can be cooked by baking, frying (cf. fish and chips), grilling, poaching (cf. court-bouillon), or steaming. Many of the preservation techniques used in different cultures have since become unnecessary but are still performed for their resulting taste and texture when consumed.
Health Benefits of Fish
Fish is highly lauded by many experts as a food with significant health benefits. This applies quite specifically to wild-caught fish, as farm-raised fish, like many commercially farmed animals, are fed many undesirable substances in less-than-ideal living conditions.
Another point of concern is heavy metal contamination. Because fish do not have a mechanism for getting rid of heavy metals from their bodies, these substances tend to accumulate in their bodily tissues. With our waters becoming increasingly contaminated, fish are beginning to contain increasing amounts of mercury. Mercury, of course, is a deadly toxin.
The reason why fish is such an important source of nutrition is that it both provides substances necessary for the human body and also reduces the risk of various diseases. For example, it has been revealed that when fish which acts as a shield in terms of health with the omega-3 acid it contains is consumed on a regular basis, it reduces the risk of heart disease and strengthens the immune system.
The Benefits of Omega-3 in Fish Oil
There are two kinds of unsaturated fatty acid in fish oil which are particularly important for our health: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). EPA and DHA are known as polyunsaturated fats and contain the important omega-3 fatty acids. Since the fatty acids omega-3 and omega-6 are not manufactured in the human body, they need to be taken in from the outside.
There is a large body of evidence relating to the benefits to human health of fish oil, the actual benefit stemming from its omega-3 fatty acid content. Despite being present in vegetable oils, these omega-3 fatty acids are less effective in relation to human health. However, marine plankton is very effective at turning omega-3 into EPA and DHA. When fish eat plankton, their constitution becomes much richer in EPA and DHA. That, in turn, makes fish one of the richest sources of these vitally important fatty acids.
Vital Benefits of the Fatty Acids Found in Fish
One of the main features of the fatty acids in fish is the contribution they make to the body’s energy production. These fatty acids carry out electron transfers by attaching themselves to oxygen in the body and permit energy to be produced for various chemical processes within it. There is therefore considerable evidence that a diet rich in fish oil helps combat fatigue and increases mental and physical capacity. Omega-3 increases the individual’s powers of concentration as much as it does his or her energy levels. There is a scientific foundation to the old saying “fish is good for the brain”: The main compound in brain fat is DHA, which contains omega-3 fatty acids.
Fish for a Healthy Heart and Arteries
The omega-3 fatty acid in fish is acknowledged to protect against cardiovascular disease by reducing blood pressure and the cholesterol and triglyceride in the blood. 2 Triglyceride is a form of fat and resembles LDL (bad cholesterol) which is high in fat and low in protein content. A raised triglyceride level, especially together with high cholesterol, increases the risk of heart disease. In addition, fish oils reduce life-threatening post-heart attack abnormal heart rhythms.
In one study by the American Medical Association, it was observed that heart attack levels in women eating five portions of fish a week fell by one-third. This is thought to stem from the omega-3 fatty acids in fish oil causing less blood clotting. The normal speed of blood in our veins is 60 kmph (37.3 mph) and it is of vital importance for the blood to be of the right viscosity and for the density, quantity and speed to be at normal levels. The worst danger for our blood—apart from normal conditions of bleeding—is for it to clot and lose the ability to flow properly. Fish oils are also effective in reducing blood clotting by preventing the thrombocytes in the blood (blood platelets that concentrate the blood in the event of bleeding) from adhering to one another. Otherwise, blood thickening can lead to narrowing of the arteries. In turn, this can lead to many organs in the body—especially the heart, brain, eyes and kidneys—receiving an inadequate blood supply, function deceleration and eventually, loss of function. For example, when an artery is totally blocked on account of clotting this can lead to heart attack, paralysis or other disorders, depending on the location of the artery.
Omega-3 fatty acids also play an important role in the production of the molecule haemoglobin, that carries oxygen in the red blood cells, and in controlling the nutrients passing through the cell membrane. They also prevent the damaging effects of fats harmful to the body.
Development of New Born Babies
Being an important component of the brain and eye, omega-3 fatty acids have been the subject of research, especially over the last 10 years, in connection with the needs of new born babies. There is a considerable body of evidence relating to the importance of omega-3 to the development of the foetus in the mother’s womb and of the new-born baby. Omega-3 is of the greatest importance for the proper development of the brain and nerves throughout pregnancy and in early babyhood. Scientists emphasise the importance of mother’s milk since it is a natural and perfect store of omega-3.
Benefits Regarding the Healthy Functioning of the Brain and Nervous System
A large number of studies have revealed the effects of omega-3 fatty acids on the healthy functioning of the brain and nerves. In addition, it has been shown that fish oil reinforcement can reduce symptoms of depression and schizophrenia and prevent Alzheimer’s disease (a brain disease which causes loss of memory and hinders day-to-day activities). For example, reductions in such problems as anxiety, stress and sleeping difficulties have been observed in individuals suffering from depression who took 1 gram of omega-3 fatty acid over a period of 12 weeks. 3
Benefits for Joint Health
The major risk in rheumatoid arthritis (a painful joint condition linked to rheumatism) is that of wearing of the joints, leading to irreparable damage. It has been proven that a diet rich in omega-3 fatty acids prevents arthritis and reduces discomfort in swollen and sensitive joints.
Omega-3 Fish Oil is One of the Best Ways to Increase Your Omega-3.
Omega-3 Fish Oil - Why Not Just Eat Salmon to Increase Your Omega-3 Levels? Omega-3 is Excellent for Your Health.
Omega-3 fish oil is excellent for your health. Fish oil contains the great types of omega-3 DHA and EPA. These are the types of Omega-3 that have all the health benefits. The best Omega-3 fish oil I know of is Salmon Oil. When it comes to increasing your omega-3 levels I think there is no better way then to take Krill Oil.
If are deficient in omega-3, so what are the benefits to your health of including the omega-3 in fish oils in your diet? It was announced in 2004 that the US Food and Drug Administration gave ‘qualified health claim’ status to both EPA and DHA reducing the risk of coronary heart disease if included in the diet. There is also evidence that a regular intake of fish oils can lower the risk of secondary and primary heart attacks. Omega-3 oils are also believed to help regulate cholesterol, as fish oils are a polyunsaturated ‘healthy’ fat. Including fish oil in your diet is believed to reduce triglyceride levels and increase the levels of the good cholesterol you need. This is beneficial to your health as high triglyceride levels are linked to an increased chance of heart disease.
Studies have also shown that consuming fish oils is very important to the human brain. They can help to improve Alzheimer’s and dementia, as the DHA can reduce the formation of plaques in the brain. It has also been shown that including fish oils in your diet can help with depression and anxiety. Omega-3 fatty acids are vital to human growth and it is very important that pregnant women consume enough fish oil as it helps their baby’s nervous system to develop properly.
It has also been suggested that omega-3 fatty acids can also help to protect against developing certain cancers; in particular prostate, breast and colon cancer. Omega-3 has also been shown to help protect against one of the most prevalent causes of blindness in older people, age-related macular degeneration. Omega-3 is said to improve circulatory problems such as varicose veins. This is because omega-3 fatty acids boost blood circulation as they increase the breakdown of fibrin, a compound that is used in the formation of blood clots and scar tissue. The omega-3 fatty acids found in fish oils have been shown to have anti-inflammatory properties and also a study found that the higher the levels of omega-3 in the body the slower the damage to DNA in the cells and possibly have anti-ageing properties.
The inclusion of omega-3 in the diet has also been shown to reduce the levels of aggression in prisoners. Studies in England and Finland showed that prisoners who were given high doses of omega-3 were less likely to be involved in assaults and violence, and also that prisoners who had been convicted for violent offenses had lower levels of omega-3 in their bodies than those inmates who were incarcerated for non-violent crimes. The theory is that omega-3 fatty acids are involved in the development of the frontal cortex of the brain, believed to be linked to personal behaviour.
Heavy metals are mostly accumulated in "greasy" fish species such as salmon and herring, as well as in "soil fishes" such as eel, carp and bream.
Fish products have been shown to contain varying amounts of heavy metals, particularly mercury and fat-soluble pollutants from water pollution. According to the US Food and Drug Administration (FDA), the risk from mercury by eating fish and shellfish is not a health concern for most people. However, certain seafood contains sufficient mercury to harm an unborn baby or young child's developing nervous system. The FDA makes three recommendations for child-bearing women and young children:
Do not eat shark, swordfish, king mackerel, or tilefish because they contain high levels of mercury.
Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Four of the most commonly eaten fish that are low in mercury are canned light tuna, salmon, pollock, and catfish. Another commonly eaten fish, albacore ("white tuna") has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week.
Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week. These recommendations are also advised when feeding fish and shellfish to young children, but in smaller portions.
Besides mercury, lead is also frequently found in fish.
Besides mercury, chlorine is also frequently found in fish.
Besides mercury, bromine is also frequently found in fish.
PCB's and dioxins
There are also issues with PCBs and dioxins.
A lot of fish eat algae and other organisms that contain biotoxins (defensive substances against predators). Biotoxins accumulated in fish/shellfish include (but are not limited to): brevitoxins, okada acid, saxitoxins, ciguatoxine and domoic acid. Except for ciguatoxine, high levels of these toxins are only found in shellfish. Both domoic acid and ciguatoxine can be deadly to humans; the others will only cause diarrhea, dizzyness and a (temporary) feeling of claustrophobia.
Some species of fish, notably the puffer fugu used for sushi, and some kinds of shellfish, can cause severe biopoisoning if not prepared properly. These fish always contain these poisons as a defense against predators; it is not present due to environmental circumstances. Particularly, fugu has a lethal dose of tetrodotoxin in its internal organs and must be prepared by a licensed fugu chef who has passed the national examination in Japan.
Parasites in fish are a natural occurrence and common. Though not a health concern in thoroughly cooked fish, parasites are a concern when consumers eat raw or lightly preserved fish such as sashimi, sushi, ceviche, and gravlax. The popularity of such raw fish dishes makes it important for consumers to be aware of this risk. Raw fish should be frozen to an internal temperature of −20°C (−4°F) for at least 7 days to kill parasites. It is important to be aware that home freezers may not be cold enough to kill parasites.
Parasite infection by raw fish is rare in the developed world (fewer than 40 cases per year in the U.S.), and involves mainly three kinds of parasites: Clonorchis sinensis (a trematode/fluke), Anisakis (a nematode/roundworm) and Diphyllobothrium (a cestode/tapeworm). Infection risk of anisakis is particularly higher in fishes which may live in a river such as salmon (sake) in Salmonidae or mackerel (saba). Such parasite infections can generally be avoided by boiling, burning, preserving in salt or vinegar, or freezing overnight. Even Japanese people never eat raw salmon and ikura, and even if they seem raw, these foods are not raw but are frozen overnight to prevent infections from parasites, particularly anisakis.