It is a well-known fact that seafood is an essential part of a balanced and healthy diet. It is high in protein, low in saturated fat and contain vitamin A as well as omega-3 fatty acids. Especially for many generations Greeks and other Mediterranean people fish dishes hold a prominent role in their cuisine.

Vitamin A, also known as retinol, is an essential nutrient that comes from eggs and meat. Fish, mussels, red and black caviar and eels, contain the active form of vitamin A critical for vision as an essential component of rhodopsin, a protein that absorbs light in the retinal receptors. Vitamin A also supports cell growth and differentiation, playing a critical role in the normal formation and maintenance of the heart, lungs, kidneys, and other organs.

Omega-3 fatty acids are thought to reduce the likelihood of atherosclerosis, hence heart disease and stroke. They are also beneficial for the brain and prevent the development of a cognitive impairment or dementia.

Omega-3 fats are found primarily in fish such as Atlantic and Australian salmon, blue-eye trevalla, blue mackerel, sardines, canned salmon and some varieties of canned tuna. Other fish, such as barramundi, bream and flathead, and seafood, such as arrow squid, scallops and mussels, are also good sources of omega-3.

But where is the catch?

What many people are not aware of is that there are certain risk factors which outweigh the health benefits of fish consumption.
Many species of fish contain certain toxic chemicals – heavy metals such as mercury, antibiotics and pesticides.
Even though mercury is a naturally occurring element, most people are exposed to it and absorb it via food. Fish take up mercury from streams and oceans as they feed. It binds to a person’s tissue proteins (such as muscle). Food processing, preparation and cooking techniques don’t significantly reduce the amount of mercury in fish.

Pregnant women – or rather, their unborn babies – are at the greatest risk, as mercury can affect their nervous system and brain development. Research is ongoing, but women should be selective about the kind and amount of fish they consume during pregnancy.

As to the question, which kinds of fish are high in mercury the answer is usually simple: large predators. Being at the top of the food chain, they absorb the mercury contained in smaller fish that they eat. Of course there are other factors as well that determine the concentration of this heavy metal such as the type of fish, location, habitat, diet and age. According to the Victorian Government website Better Health Channel the species that contain higher levels of mercury include: shark, ray, swordfish, barramundi, gemfish, orange roughy, ling, and southern bluefin tuna. Low mercury levels are generally found in shellfish (prawns, lobsters and oysters), salmon, canned tuna, and sardines.

However, the human body does have the capacity to clear out the mercury over time. So people only go over the safe levels if they eat a lot of high mercury-containing fish regularly over many months.

What happens with other chemicals, like antibiotics and pesticides?

Farmed fish, as opposed to fish caught in the open seas, can be contaminated by antibiotics and other chemicals fish farmers use to control diseases.
Urban waterways on the other hand can become polluted with chemicals coming from industrial products which can eventually build up in fish.

Certain chemicals tend to concentrate in the fatty parts of a fish’s body. For instance, eels have a higher fat content than other fish and so tend to carry higher amounts of these chemicals.

If a person eats large amounts of contaminated fish, the contaminants may affect their health.

To avoid this risk, experts recommend eating smaller, younger fish – as these are likely to have fewer pollutants than older, larger fish – but also cleaning and cooking fish properly. This means removing skin, fat and internal organs before cooking, because, as mentioned above, some chemicals concentrate in the fatty parts. Remember to always go for fresh and wild when you can.

Here’s a healthy and easy fresh salmon salad with chickpeas and tomatoes recipe to begin with:

Ingredients:

6 tablespoons olive oil, divided
6 salmon fillets
2 cups chickpeas from two cans, drained, rinsed
1 1/2 cups chopped tomatoes
1/4 cup small black olives
2 tablespoons chopped fresh Italian parsley
2 tablespoons fresh orange juice
1 tablespoon fresh lemon juice
1 tablespoon salt-packed capers, rinsed, or drained capers in brine
1 tablespoon grated orange peel
1 teaspoon grated lemon peel
2 tablespoons fresh basil leaves, torn if large

Method:

1. Heat 1 tablespoon oil in each of 2 heavy large skillets.
2. Sprinkle salmon with salt and pepper.
3. Add 3 fillets to each skillet and cook until almost cooked through, about 3 minutes per side. Cool slightly.
4. Heat remaining 4 tablespoons oil in large skillet over medium-high heat.
5. Add chickpeas and all remaining ingredients except basil. Stir until warm. Season with salt and pepper.
6. Divide chickpea mixture among 6 plates.
7. Tear salmon into pieces; scatter over chickpeas. Garnish with basil leaves and serve.

*Sources: abc.net.au, betterhealth.vic.gov.au, sbs.com.au, heartfoundation.org.au, seriousseats.com, jamieoliver.com, bonappetit.com, eatingwell.com, foodandwine.com