Many species of fish are consumed as food in virtually all regions around the world. Fish has been an important source of protein and other nutrients for humans from time immemorial.
In culinary and fishery contexts, fish may include shellfish, such as molluscs, crustaceans and echinoderms. English does not distinguish between fish as an animal and the food prepared from it, as it does with pig vs. pork or cow vs. beef. Some other languages do, as in the Spanish peces versus pescado. The modern English word for fish comes from the Old English word fisc (plural: fiscas) which was pronounced as it is today. English also has the term seafood, which covers fish found in the seas and oceans as well as other marine life used as food.
Research over the past few decades has shown that the nutrients and minerals in fish, and particularly the omega-3 fatty acids found in pelagic fishes, are heart-friendly and can make improvements in brain development and reproduction. This has highlighted the role for fish in the functionality of the human body.
Fish is the most common food to obstruct the airway and cause choking. Choking on fish was responsible for about 4,500 reported accidents in the UK in 1998.
If fish and shellfish inhabit polluted waters, they can accumulate other toxic chemicals, particularly fat-soluble pollutants containing chlorine or bromine, dioxins or PCBs. Fish that is to be eaten should be caught in unpolluted water. Some organisations such as SeafoodWatch, RIKILT, Environmental Defense Fund, IMARES provide information on species that do not accumulate much toxins/metals.
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. Home freezers may not be cold enough to kill parasites.
Traditionally, fish that live all or part of their lives in fresh water were considered unsuitable for sashimi due to the possibility of parasites (see Sashimi article). Parasitic infections from freshwater fish are a serious problem in some parts of the world, particularly Southeast Asia. Fish that spend part of their life cycle in brackish or fresh water, like salmon, are a particular problem. A study in Seattle, Washington showed that 100% of wild salmon had roundworm larvae capable of infecting people. In the same study farm-raised salmon did not have any roundworm larvae.
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. In Japan it is common to eat raw salmon and ikura, but these foods are frozen overnight prior to eating to prevent infections from parasites, particularly anisakis.

Nutritional value

Intermediate Technology Publications wrote in 1992 that “Fish provides a good source of high quality protein and contains many vitamins and minerals. It may be classed as either whitefish, oily fish, or shellfish. Whitefish, such as haddock and seer, contain very little fat (usually less than 1%) whereas oily fish, such as sardines, contain between 10–25%. The latter, as a result of its high fat content, contain a range of fat-soluble vitamins (A, D, E and K) and essential fatty acids, all of which are vital for the healthy functioning of the body.

20 Amazing benefits

1. It Lowers Risk of Heart Disease

According to a review published in the American Journal of Cardiology, fish consumption is associated with a lower risk of fatal and total coronary heart disease. Fish is high in heart-healthy omega-3 fatty acids which can reduce inflammation, help protect your heart, and stave off chronic disease.

2. It Reduces Risk of Alzheimer’s Disease

Fish is also a dietary essential for your brain. According to a 2016 study published in the Journal of the American Medical Association, moderate seafood consumption was linked with a lower risk of Alzheimer’s Disease. The study found that those who consume fish regularly had more grey brain matter, which reduces brain shrinkage and deterioration that can lead to brain function complications. Although they noted that seafood consumption was also correlated with higher levels of mercury in the brain, it was not correlated with brain neuropathy.

3. It Can Help Lower Symptoms of Depression

This seafood is also amazing for your mental health. The Journal of Psychiatry & Neuroscience found that fish oil can help improve symptoms of depression when taken with a selective serotonin reuptake inhibitor (SSRI), a type of antidepressant. Although there are reports of fish oil decreasing symptoms of depression on its own, there still needs to be more research conducted to prove this claim.

4. It’s a Great Source of Vitamin D

According to The National Institutes of Health, fish are high in vitamin D, and are considered one of the best dietary sources for this essential nutrient. According to the NIH, vitamin D is beneficial for calcium absorption for bone health and growth. Because 70% of the U.S. population does not meet the Estimated Average Intake (EAR) of vitamin D every year, it will certainly be helpful if you add more of this nutrient-dense food to your diet.

5. It Helps Improve Vision and Eye Health

The Agency for Healthcare Research and Quality found that omega-3 fatty acids are beneficial to improving vision and eye health. This is because the brain and eyes are heavily concentrated in omega-3 fatty acids and need them to maintain their health and function, according to the AHRQ’s findings. Fish is one of the best sources of these good fats.

6. It Can Help You Sleep Better

If you have trouble falling or staying asleep, eating more fish may do the trick. According to a study published by The Journal of Clinical Sleep Medicine, increased consumption of fish improved quality of sleep for most subjects. Researchers suspect that this is due to fish’s high concentration of vitamin D, which aids in sleep, according to the study.

7. It Helps Fight Acne

Whether you have hormonal or adult acne, fish can help alleviate your skin. A study published by BioMed Central noted that fish oil is beneficial to clearing skin for people with moderate to severe acne.
8. It’s Helpful in Alleviating Rheumatoid Arthritis
If you suffer from rheumatoid arthritis, which is chronic inflammation of your joints, eating more fish can help alleviate the swelling and pain. The American College of Rheumatology found that higher consumption of fish actually lowers disease activity in rheumatoid arthritis.

9. It’s a Lean Meat

The American Heart Association noted that fish is a great source of protein without the high saturated fat content that many other types of meat have. The AHA recommends eating two servings of fish per week, preferably fatty fish, which have a higher omega-3 fatty acid content.

10. It Helps Lower Cholesterol

The Baylor University Medical Center Proceedings noted that the omega-3 fatty acids found in fish oil assist in lowering LDL levels (also known as “bad” cholesterol levels) in the body. The omega-3 fatty acids in fish are known to help lower cholesterol-building lipids in the blood, according to the university’s findings.

11. It Alleviates PMS Symptoms

Fish can also assist with premenstrual symptoms in women, according to a study published by the Journal of Psychosomatic Obstetrics & Gynecology. The study found that the interference of premenstrual symptoms in the daily lives of women heavily reduced when they increased their ingestion of omega-3 fatty acids, which is found in most fish.

12. It Decreases Risk of Heart Failure

Fish has a very heart-healthy reputation, and for good reason. A study conducted by the Division of Aging at Brigham and Women’s Hospital’s Department of Medicine showed that a moderate consumption of fish will help lower risk of heart failure, due to its high concentration of heart-healthy omega-3 fatty acids.

13. It Lowers Risk of Strokes

Another way that fish helps your brain health is by decreasing the risk of strokes. According to The British Medical Journal, the high omega-3 fatty acid content in fish also helped lower risk of strokes in subjects of the study.

14. It Decreases the Risk Of Autoimmune Disease

According to a study published in the journal Nutrition and Diabetes, eating fatty fish can actually help prevent autoimmune diseases such as type 1 diabetes. Fish’s high vitamin D content assists in your body’s immunity and glucose metabolism, according to the study.

15. It Helps Treat Liver Disease

Omega-3 fatty acids found in fish have also been shown to help treat liver disease. A study by Columbia University showed that omega-3 helps break down triglycerides and fatty acids in the liver, lowering the risk of fatty liver disease.

16. It Speeds Up Your Metabolism

Research from the Department of Human Health and Nutritional Sciences at the University of Guelph found that omega-3 fatty acids, which are abundant in fish, have a positive effect on your metabolism. The study noted that this healthy fat boosted resting and exercise metabolic rates, as well as fat oxidation, in older women.

17. It Helps Athletes Recover Faster

Fish contains nutrients that are extremely beneficial in helping athletes recover from fatigue and help in muscle regeneration. A study published in Sports Medicine showed that vitamin D and omega-3 fatty acids, which are heavily prominent in most fatty fish, play a big role in post-exercise muscle regeneration and fatigue recovery. After a particularly rigorous sweat sesh, be sure to load up on one of the 16 Post-Workout Snacks Fitness Experts Swear By.

18. It Lowers Blood Pressure

If you have high blood pressure, incorporating more fish into your diet may help lower it. A study published in the journal Circulation found that fish oil is helpful in lowering blood pressure due to its high concentration of omega-3 fatty acids.

19. It Increases Concentration and Attention Span

Fish has also been shown to help with concentration and attention in adolescents. A study published in Nutritional Journal found that students between the ages of 14 and 15 who ate fatty fish over other meats had higher rates of concentration and were able to pay attention longer in comparison to those who ate less of it.

20. It Lowers Risk Of Cancer

Fish can even lower risk of certain cancers, according to a study by The American Journal of Clinical Nutrition. The study showed that people who had a high consumption of fish actually had a lowered risk of digestive cancers, such as oral cavity, pharynx, colon and pancreas cancers, in comparison to those who ate lower amounts of fish.