日本人平均壽命84歲，是最長壽的國家、愛斯基摩人罹患心血管疾病的比例偏低，這些都和常吃魚的習慣息息相關，魚類除了富含豐富的蛋白質，且夾帶的脂肪以Omega-3 不飽和脂肪酸為主，是人體成長所需的必備營養素。 不過，現代人生活忙碌，很少有時間到生鮮市場買新鮮的魚回家烹調，於是「魚罐頭」成為很多婆婆媽媽、小資女的選擇，但有些民眾買了之後，又會怕魚罐頭沒甚麼營養，如今，美國醫學專家打破民眾的迷思。
原始資料來源：The New York times (OCTOBER 7, 2015):
Does canned fish like tuna and salmon have the same nutritional value as fresh fish?
The canned products are certainly cheaper, available and convenient.
Yes, fresh and canned fish have roughly the same nutritional value, according to experts and the United States Department of Agriculture’s National Nutrient Database. And whether to eat one over the other isn’t an obvious choice, because each has advantages and disadvantages, said Alice Lichtenstein, a professor at Tufts University’s Friedman School of Nutrition Science and Policy.
Canned tends to be cheaper and easier than fresh, with a longer shelf life. But it also tends to have more sodium than fresh, she said, and many people prefer the taste of fresh.
Canned fish is also more likely to be wild than farmed, said Kristin Kirkpatrick, a registered dietitian and manager of nutrition services at the Cleveland Clinic Wellness Institute; some types of farmed fish have been found to be high in pollutants. Plus, canned fish such as sardines generally provide more calcium, because the calcium-rich bones are softened by processing and therefore more likely to be eaten.
In terms of mercury levels, a particular concern for pregnant women, Dr. Lichtenstein said she suspected that canned fish like salmon probably contains less mercury than fresh, because smaller-size fish, which carry less mercury than larger ones, are more likely to end up in cans.
If you choose canned, fish canned in oil is more likely than fish packed in water to retain more omega-3 fatty acids, considered good brain food, Ms. Kirkpatrick said, because the oil helps keep the nutrients in the fish. Oil adds extra calories, but if packing in oil means someone will eat fish they wouldn’t otherwise, it’s worth it, Dr. Lichtenstein said.
“Bottom line,” Ms. Kirkpatrick said, “it’s important to get your omega-3s, and one of the easiest and most affordable ways to do that is to go canned. You won’t be skimping on nutrition.”