Governments regulate the amount of heavy metals allowed in seafood, but how well do labs test for such contaminants? Announced in a release on November 24, the European Union put 57 food laboratories from 29 countries around the world to the test. Grade: passing.

Each laboratory received a seafood sample without knowing the levels of heavy metals present, and was asked to measure and report the values back to the European Commission Joint Research Centre. The review states that most labs correctly measured maximum levels of lead, cadmium, and mercury in seafood - although participants tended to underestimate the content of total arsenic.

In Europe, maximum levels for lead, cadmium, and total mercury in food are laid down in legislation, varying from 0.5 to 1.0 mg per kg for different seafood. No maximum levels for arsenic have been set yet by European legislation, due to "a lack of information about reliable analytical methods" for measuring arsenic, states the release.

The release states that results should boost consumer confidence that the fish they eat meets regulations. But with overfishing and rising heavy metal levels in seafood, what are the best types of fish to eat, both for your body and the planet? On November 3, men's online magazine Ask Men published a roundup of seafood that packs a punch in terms of protein and amino acids, yet reportedly contains reduced heavy metal levels and has healthier populations compared to larger species, such as shark and tuna.

Sardines - Some of the most nutrient-dense food on the planet, sardines contain large amounts of omega-3 acids, which help regulate and lower blood cholesterol. Also, due to their miniscule size and short lifespan, they absorb very few contaminants and contain trace amounts of mercury.

Mackerel - One of the best sources of omega-3 fatty acids (twice that of salmon) and an excellent source of selenium to boost your immune system. Mercury levels are considered low for Northern Atlantic mackerel.

Tilapia - A healthful, low-priced choice thanks to low mercury and cholesterol levels, yet it is still relatively high in omega-3s. The Environmental Protection Agency advises sticking with US-based tilapia over its Asian and Latin American counterparts.

Haddock - Popular in fish and chips, haddock contains high levels of magnesium, vitamin B6, niacin, and phosphorus.

Seaweed - A rich plant source of vitamin C, zinc, iodine, and even protein, seaweed is packed with amino acids and is said to bolster metabolism and cure impotence.

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