Salmon and Beef: What's Safe to Eat?
Here's a look at the science behind the scares
Amid the flurry of headlines about the food industry, it's a challenge to
figure out what is safe to eat: Is mad cow disease a real threat? Does farmed
salmon cause cancer?
Many consumers are racing to buy organic foods to avoid potential toxins in
their grocery carts. But are we overreacting, or is there really cause to shun
our food supply?
When it comes to two of the most recent foods called into question -- beef
and salmon -- it boils down to a matter of risk vs. benefit. To help you decide
whether these foods are for you, let's take a serious look at the science
behind the headlines.
The Salmon Scare
A report in the January issue of the journal Science touched off alarm that
farmed salmon contained levels of polychlorinated biphenyls (PCBs, a kind of
dioxin) that could be harmful. The concern over PCBs stems from their role as a
likely carcinogen in humans, based on studies in animals.
In an ideal world, there would be no PCBs. But unfortunately, they exist in
the air that we breathe and in many foods we eat, including chicken, butter,
and both wild and farmed salmon. PCBs get into wild salmon from the other fish
they eat and into farmed salmon from their feed (which contains many of these
The FDA has set the safe upper limit for PCBs at 2000 parts per billion
(ppb). Farmed salmon averages 27 ppb, well below that limit. The controversy
has come about because another branch of the government, the Environmental
Protection Agency (EPA), has set a much lower safe limit for PCBs in food --
4.5 times lower, in fact.
Keep in mind that these two agencies are charged with different functions.
The EPA sets limits meant for recreationally caught fish, while the FDA's
limits are intended for fish sold commercially. The FDA's higher limit is also
supported by the World Health Organization and the European Union.
Although the amount of PCBs found in most fish is only 1/80th of the FDA
safe level, ''The farmed salmon industry is working to further reduce PCBs in
fish feed while maintaining the healthful omega-3 fatty acid content,'' says
Alex Trent, executive director for the industry group Salmon of the
The American Heart Association maintains that eating two servings a week of
oily fish (like salmon) can help healthy adults ward off sudden cardiac death,
thanks to the protective effects of omega-3 fatty acids. The best source of
these omega-3 fatty acids is farmed salmon, though they're also found in
flaxseed, walnuts, soybeans, and oils made from these products.
Many longstanding studies have documented the health benefits of a diet rich
in omega-3 fatty acids and their role in guarding against heart disease. More
recent studies have indicated that omega-3s may even help keep your mind agile
and protect against Alzheimer's disease. And salmon, like other fish, is an
excellent, low-fat source of protein that many people enjoy eating.