Yes, canned tuna can be a good source of omega-3 fats, but how much omega-3s are contained in the can of tuna you purchase can vary considerably. Here's what you need to know to choose the can with the most omega-3s.
First of all, several different varieties of tuna are canned. Skipjack, Bluefin and Yellowfin (called Ahi in Hawaii) tuna are canned and sold as "light meat," while Albacore (also called Longfin tuna , Tombo Ahi, and Ahi Palanacan) is the only tuna that can be labeled premium "white meat".
Nutritionally, these different types of tuna are quite similar—except for their fat content, which can vary by as much as 2 grams per ounce depending on the season and water temperature where the fish was caught.
So, even if you buy the same kind of tuna every time, be sure to check the Nutrition Facts label on the can you are considering purchasing—the information presented here must tell you what nutrients the fish packed in this can contains.
To get the most omega 3 fats from your canned tuna, choose water-packed tuna rather than oil-packed. The oil mixes with some of the tuna's natural fat, so when you drain oil-packed tuna, some of its omega-3 fatty acids also go down the drain. Since oil and water don't mix, water-packed tuna won't leach any of its precious omega-3s.
Canned in water and drained, 6 ounces of light meat tuna typically provide a little less than .5 gram of omega-3 fatty acids, while light tuna canned in oil and drained provides a little more than .3 grams of omega 3.
One assay found that 100 grams (about 3 ½ ounces ) of light tuna canned in water and drained contained 0.272 grams of omega-3 fatty acids, derived from EPA (0.047g), DHA (0.223g), and ALA (0.002g). Tuna canned in oil and drained contained almost a third less omega 3s: 100 grams of light meat tuna canned in oil and drained provided 0.202 grams of omega-3 fatty acids in the form of EPA (0.027g), DHA (0.101g), and ALA (0.074g).
Specialty brands of Premium or "Gourmet" canned Pacific Albacore tuna may be your best choice for omega-3 oils among all the types of canned tuna. These smaller, often family-owned tuna fisheries catch their tuna in the cold waters of the Pacific by hook and line trolling. As soon as a fish is hooked, it is brought aboard and fresh-frozen. Large commercial fisheries typically catch their tuna in the warmer waters of the Atlantic using "long lines" that lay deep in the water and are harvested only every 24 hours.
The way the tuna is processed also differs. The larger commercial canneries, such as Starkist®, cook their fish twice. First, they bake the fish whole on a rack, which results in a loss of natural beneficial oils. Then the fish is de-boned and put into the can, along with flavorings like vegetable broth, and additives such as pyrophosphate or hydrolyzed casein. The cans are sealed, and the fish is cooked again. This process allows the companies to de-bone the fish fillets faster and produce a higher volume of product. Specialty products are typically packed into the can raw and cooked only once, so all their natural juices and fats remain in the finished product. Tested specialty brands have been found to contain up to 2.97 grams of omega-3 fats in a 100 gram (3.5 ounce) serving.
|Type of Fish||Total Omega 3 Fat||EPA (unique type of Omega 3 Fat)||DHA (Unique type of Omega 3 Fat)|
|fresh bluefin tuna, baked, 6 ounces||2.5 grams||0.6 grams||1.9 grams|
|fresh albacore tuna, baked, 6 ounces||2.6 grams||0.5 grams||1.7 grams|
|fresh skipjack, baked, 6 ounces||2.7 grams||0.7 grams||2.0 grams|
|Light tuna, canned in water, 6 ounces||0.46 grams||0.08 grams||0.38 grams|
|Light tuna, canned in oil, 6 ounces||0.34 grams||0.05 grams||0.38 grams|
|Starkist TM Albacore tuna, canned in water, 6 ounces*||1.35 grams||data not available||data not available|
|Papa George Gourmet Albacore tuna, canned in olive oil, not drained, 6 ounces||8.1 grams||2.6 grams||5.5 grams|
*The brand name data is derived from Starkist's website and lab reports supplied by these two specialty tuna companies, see Sources below.
Sources: Am J Clin Nutr, January 2000 Supplement; 71:179S-188S.
USDA Nutrient Composition Database: http://www.nal.usda.gov/fnic/foodcomp/Data/index.html
Food Processor for Windows, Version 7.60, Database Version December 2000, ESHA Research, Salem, OR.
Simopoulos A, Kifer RR, and Martin RE (Eds). (1986). The Health Effects of Polyunsaturated Fatty Acids in Seafoods. Academic Press, New York. Starkist Tuna: www.Starkist.com
Papa George Gourmet Albacore, Seattle, WA. www.PapaGeorgeTuna.com Phone: 206-255-4203. Product lab analysis provided by Food Products Laboratory, Portland, OR.