Tuna and salmon are good sources of fish oil and Omega-3 fatty acids. Salmon has comparatively more calories and fats while tuna is richer in protein. At over 1 billion pounds per year, tuna consumption in the U.S. is more than twice that of salmon. Salmon is more expensive (especially wild caught salmon) and is more likely to be considered a delicacy. Tuna has more mercury content so it's not recommended for pregnant women and young children.
Tuna are a group of large, sleek, predatory fish found in the open oceans of the world. Salmon are a family of fish that breed in rivers but live most of their adult lives at sea. Salmon have orange or pink flesh. They move from the ocean back to the stream where they were born for breeding.
- Salmon is high in protein, omega-3 fatty acids and vitamin D content and a great source of cholesterol (23–214 mg/100 g).
- Wild salmon is an important source of Omega-3 (DHA and EPA), which are essential for brain function and structure.
- Farmed salmon may contain high levels of dioxins and PCB (polychlorinated biphenyl) levels and lower Omega-3 levels when compared to wild salmon. However, according to a study published in the Journal of the American Medical Association, the benefits of eating even farmed salmon still outweigh any risks imposed by contaminants. The type of omega-3 present may not be a factor for other important health functions.
Tuna is a good source of omega-3 fatty acids (300mg per serving). However, the level of omega-3 in canned tuna is highly variable, since the type if manufacturing can destroy much of the omega-3 oils in the fish. Tuna is also a good source of protein.
Tuna also contains varied levels of Mercury as the mercury distribution in farmed tuna is inversely related to the lipid content, suggesting that tuna with higher natural fat content might help reduce the amount of mercury intake.
Advantages of Salmon over Tuna
Due to the risk associated with the presence of mercury, women of childbearing age and children should avoid more taking more than 6 ounces of tuna per week. Wild caught salmon is safe and has about 300 to 650 mg of omega-3 fatty acids. Salmon bones are soft to be eaten. Hence, they are a good source of calcium. The lower risk of presence of mercury and the additional nutritional benefit make canned salmons a better choice over canned tuna.
Advantages of Tuna over Salmon
Tuna has lower calories, fat (both saturated and polyunsaturated fat) and cholesterol content per 100g than salmon. Tuna also has more protein.
What to buy
Americans eat over 1 billion pounds of canned and pouched tuna every year. Only coffee and sugar are consumed in quantities higher than tuna. The canned tuna market is over $1 billion every year. Salmon is more expensive. About 500 million pounds of salmon are harvested every year with a commercial value of over $1.5 billion. In the U.S. in 2009, salmon had an 18.1% share of seafood sales in the West, 13.6% in the Central region and 10.6% in the East, where other finfish species like cod are more popular. Salmon fishing in the U.S. is primarily done on the west coast: Alaska, Washington, Oregon and California.
The Best Salmon
Wild caught pink or sockeye salmons from Alaska are the best as their level of contaminants is low. They are also sustainably caught using Drift Gillnet, Purse Seine or Troll. Salmons farmed in open net pens are to be avoided due to environmentally-unfriendly breeding methods and use of PCBs (polychlorinated biphenyls). The next choice in salmons would be those wild caught from the states of California, Oregon and Washington.
Albacore, skipjack or yellowfin tuna caught in the waters of Canada and US Pacific using troll, pole and line are the best choices. The mercury level in adult tunas is high. Young tunas less in mercury are caught using these methods and they are considered to be safer. Tunas caught using longlines are adults and are hence to be avoided. A health alert has been issued by the FDA to avoid other types of canned tuna due to the risk of elevated mercury level. Canned chunk light tuna (skipjack) (0.12ppm of mercury) are found to have about 1/3 of the average mercury levels found in canned albacore tuna (solid white tuna) (0.32ppm of mercury).
The FDA recommends a limit of 12oz. of fish by women in childbearing age and children due to presence of low level of mercury in most fish. Pregnant women are best adviced not to consume sushi, or fish in any raw form.
Interior Alaska Fish Processors Inc., based in Fairbanks, AK, issued a voluntary recall of its Santa's Smokehouse brand hot-smoked vacuum packed salmon products in August 2012 because an error in the label indication. The label indicates that the fish can be refrigerated below 38 F but in fact has to be frozen till consumption. The improper storage might lead to Clostridium botulinum that might cause botulin toxin leading to paralysis. Moon Marine USA corporation, a Cupertino based company recalled 58,828 pounds in of its "Nakaochi Scrape" - tuna backmeat scraped off the bones of the fish and sold in a frozen, ground state in April 2012. The yellowfin tuna product was found to be a common food source among Salmonella Bareilly outbreak victims.