In 2015, the World Health Organization released a groundbreaking study on the health risks of processed meat, breaking the hearts of hot dog lovers everywhere. Their International Agency for Research on Cancer (IARC) classified processed meat as a carcinogen, specifically targeting these foods after epidemiological studies showed the development of cancer in exposed humans. Colorectal, pancreatic, prostate and stomach cancer have all been linked to eating processed meats.

"The current evidence suggests the higher [the] intake of processed meat, the higher the risk of chronic diseases and mortality," said Frank Hu, a professor at the Harvard T.H. Chan School of Public Health.

So we can all agree that we should cut back on salami, bacon, sausages, and deli meat — but what about smoked or cured fish? The lox on our bagel, a hot-smoked whitefish at our favorite Jewish deli, or the kippered herring in a traditional Scottish breakfast — are all of these delicious, smoky fish also off the table?

A dried, preserved, smoked fish on white background Smoked Atlantic mackerel, anyone? (Photo: Luc Viatour [CC by SA 3.0]/Wikimedia Commons)

It depends. Smoking is one of the oldest forms of food preservation, and our ancestors have been doing it all over the globe for a long time. The main steps in preserving involve salting (either by a brine or dry salt), smoking (either hot or cold), packaging and storing. Smoking is a shortcut that combines salting, drying, heating and smoking all in one. As you might expect, cold smoking doesn't actually cook the fish or remove food pathogens, so it's usually found in refrigerated aisles in the U.S.

While you'll find hot-smoked eel in the Netherlands, Yarmouth bloaters for breakfast in England, and the smoked haddock dish kedgeree in India, we in the U.S. are not quite so adventurous. Most of our fishy delights are hot-smoked, due to time restraints and ease, besides the versatile salmon, mackerel and herring, which can go both ways.

But how does this dish with seafaring origins compare to, say, a pot of canned meat? That depends on what you're most concerned about in your diet. Fish is a great source of protein, B vitamins, vitamin D, magnesium and selenium. It's also chock full of omega-3 fatty acids, which are linked to a lower risk of heart disease and Alzheimer's disease, as well as other health benefits.

box of smoked fish from Armenia Varieties of smoked fish can be found all over the world, including this box of dried fishy delights from Lake Sevan in Armenia. (Photo: Arthur Chapman [CC by 2.0]/Flickr)

But smoked fish is also full of sodium. Three ounces of cooked fresh salmon has just 50 milligrams, while the same serving of smoked fish contains 666 milligrams — that's more than 1/3 of a day's worth! Too much salt in your diet can lead to high blood pressure, which is a risk factor for heart disease and stroke.

Another thing to keep in mind are the preservatives nitrate and nitrite, which are byproducts of the smoking process and often added to prevent Listeria and other foodborne pathogens, as well as preserve the color of the meat. Nitrates occur naturally in nature — for instance, celery powder — but once they enter our digestive system, they convert to nitrites. In certain conditions in the human body, nitrites can morph into molecules that cause cancer. Even though it'll have a shorter shelf life, try to look for fish that doesn't have these additives.

For the pregnant, elderly and people with weakened immune systems, it might be best to avoid cold-smoked fish. It's smoked at a temperature that isn't hot enough to kill potentially bad bacteria, nor is it hot enough to actually cook the fish. The Centers for Disease Control and Prevention recommends certain vulnerable people stay away from cold-smoked fish unless it's canned, shelf-stable or cooked to an internal temperature of 165 degrees F (for instance, in a pasta or casserole dish).

All that to say, fish is an excellent protein source, and overall healthier than red meats, especially processed meats. If you can't live without your smoked salmon, make sure you keep it properly refrigerated, buy it from a trustworthy source, and consume by the "use by" date. And if you eat it often, make sure you balance all that sodium with plenty of fruits and vegetables. Moderation, as always, is key.

How safe is cured, smoked or salted fish?
We've read about the harmful health effects of eating processed meats. But what about their fishy counterparts?