AVEIRO, PORTUGAL: Traditional canned fish mackerel, tuna, sardines, cod roe, stacked on shelves for sale in food shop in Aveiro, Portugal.  (Photo by Tim Graham/Getty Images)
Food - Drink
Why You May Want To Choose Canned Tuna Over Fresh
Although seafood can be a healthy choice, rising levels of mercury in various sea creatures present a real health concern, especially for children and pregnant women. Consuming too much mercury can harm motor skills, logic, and memory, and even cause depression, anxiety, and a greater propensity toward heart attacks.
High levels of mercury found in fresh tuna have turned into a selling point for canned tuna, which is generally made from smaller fish caught within their first year of life. This means the fish has less time and space to absorb mercury, and per Food Standards Australia and New Zealand, "eating a can of tuna per week is perfectly fine, even for pregnant women."
The amount of mercury in a 3 oz can of Light Tuna is 10.71 micrograms, while a 3 oz canned Albacore Tuna contains 29.75 micrograms. While Light Tuna has significantly less mercury, Albacore Tuna has about the same amount as most fresh tuna, which is generally said to have 30.43 micrograms per 3 ounces.