The question: I know processed meat isn't healthy. What about smoked salmon?
The answer: Smoked salmon has nutritional advantages and drawbacks. Like fresh salmon, it's a good source of protein, B vitamins, vitamin D, magnesium and selenium. Smoked salmon also contains plenty of DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), omega-3 fatty acids linked to a lower risk of heart disease, macular degeneration and Alzheimer's disease.
On the downside, smoked salmon delivers a hefty dose of sodium. Three ounces of smoked salmon, for example, contains 666 milligrams of sodium, more than one third of a day's worth. The same serving size of cooked fresh salmon has 50 milligrams.
Before fish is smoked, it's cured by adding salt in the form of a brine (a mixture of salt, water and spices) or salt crystals. Salting reduces the moisture content of fish, which helps extend its storage life. It also helps prevent the growth of microbes that could cause food poisoning.
Most smoked salmon is cold smoked, meaning it's smoked at a temperature that's not hot enough to cook the fish, nor hot enough to kill potentially harmful bacteria. One concern is Listeria monocytogenes, a bacteria that can cause a rare but serious food poisoning especially among pregnant women, the elderly, and people with weakened immune systems.
Hot smoked salmon is smoked at temperatures around 80 C. It's fully cooked, lighter in colour and flakier than cold smoked salmon. Even though it's cooked, food safety issues can arise if improper food handling practices occur prior to, during or after the smoking process.
Because Listeria can survive, and sometimes grow, on foods stored in the refrigerator, people at high risk for Listeria food poisoning should avoid eating refrigerated smoked fish. Smoked fish is safe to eat, however, if it's fully cooked to an internal temperature of 74 C (165 F), such as in a pasta dish or casserole.
There's also concern that eating smoked foods can increase cancer risk. There is some evidence, albeit weak, that high intakes of smoked foods – in particular meat and fish – increase the risk of stomach cancer. Smoked fish contains nitrates and nitrites, byproducts of the smoking process. (Some brine solutions can also contain sodium nitrite.) The concern is that nitrites and nitrates can be converted in the body to N-nitroso compounds, which have been shown to cause stomach cancer in lab animals.
If you enjoy eating smoked salmon, buy it from a reliable manufacturer, consume it by the "use by" date, and keep it properly refrigerated. If you eat it frequently, balance your sodium intake and include plenty of fruits and vegetables in your daily diet. A high intake of fruits and vegetables is associated with protection from stomach cancer.
Leslie Beck, a registered dietitian, is the national director of nutrition at BodyScience Medical. She can be seen every Thursday at noon on CTV News Channel'sDirect (www.lesliebeck.com).
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