Today, I saw that albacore tuna was on sale at my local grocery store. I was tempted to get it, but a nagging feeling in my head said I should hold off; I already had two meals with salmon the week before. That feeling comes from the fact that for several years now, I’ve heard that although fish is good for you, eating too much of it can expose you to too unhealthy levels of mercury and other contaminants.
That’s too bad, because fish is typically a low fat source of protein and they’re high in healthy omega-3 fatty acids. The fish that are higher in fat content, like sardines, are just about the only natural food sources of vitamin D. Plus, I love my sushi!
In this post, I want to look at the nutrient content of some of the most commonly consumed fish and then develop a general rule for how much is a reasonable amount to eat each week. I also want to see if farmed fish have nutritional or other benefits over wild or vice versa.
The most popular fish in the U.S. (Excluding Nemo and Dory)
While the National Oceanic and Atmospheric Administration (NOAA) Fisheries site says that in 2010 shrimp was the number one seafood consumed in the U.S., the most popular fish was tuna. Canned tuna specifically, at 2.5 pounds per year per person.
Salmon, a staple out here in the Northwest, was next, at 1.84 pounds per year per person, followed by tilapia catfish and cod. I was surprised that Cod was so far behind at just 0.44 pounds. Cod is the main type of fish used in fish and chips. I guess in the U.S. we haven’t yet developed quite the devotion this U.K. staple.
How do fish measure up nutrient-wise?
According to a can of tuna that I just happen to have in my cabinet, a 3/4 cup serving (161 grams—the whole can) has 240 calories, 4.5 grams of fat, and a massive 48 grams of protein. That’s a lot of protein for such a small serving.
But how about Salmon? I looked at Nutrition Data on Self.com to find the details. There I found that 154 grams of cooked Atlantic wild salmon, a half fillet, has 180 calories, 12.5 grams of fat, and 39.2 grams of protein. It’s also a great source for meeting the recommended daily amounts of these vitamins and minerals: thiamin (28%), riboflavin (44%), niacin (78%), vitamin B6 (73%), vitamin B12 (78%), pantothenic acid (30%), phosphorus (39%), potassium (38%), copper (25%), and selenium (103%).
Okay, I’m sold. Salmon not only tastes delicious, but it has tons of nutrients, is low in calories, and around 90 percent of its fat is unsaturated—the good kind of fat.
You are what you eat (and perhaps so are fish)
As I mentioned, the nutritional data I looked at was for a wild Atlantic salmon. I wondered: Is there a difference between farmed and wild in nutrient content?
Looking at Self.com’s nutrition data, I found that a ½ fillet serving, or 178 grams, of cooked farmed Atlantic salmon has 367 calories, 22 grams of fat, only 75% of which is unsaturated. It has 39.2 grams of protein, and compared to the wild salmon, has much lower levels of riboflavin and copper.
So the farmed salmon is much higher in calories and fat—almost double for both. More of that fat is the unhealthier saturated fat. And you lose out somewhat on vitamins and minerals. I’m sticking with wild salmon.
The Cleveland Clinic backs up these numbers in their article Fish Faceoff: Wild Salmon versus Farmed Salmon. The article also notes that while farmed fish may be cheaper, it frequently comes with contaminants and health effects from exposure to carcinogens along with antibiotics often used in farmed fish. They recommend eating wild salmon in moderate amounts because all fish swim in water that may be polluted.
How much fish should you eat each week?
Many people, including me, worry that eating fish risks ingesting too much mercury or other contaminants. So what can you do to minimize that risk? What fish are safe to eat and how much should we consume each week. What about pregnant women and children? Should they consume less fish?
According to the same NOAA Fisheries site, you should eat fish like salmon, anchovies, herring, sardines, cod, trout, and Atlantic and Pacific mackerel (not King mackerel) that are lower in mercury. Reduce or completely avoid fish that are high in mercury, such as shark, swordfish, king mackerel, or tilefish. WebMD spoke to experts on this topic, including the Environmental Protection Agency and the US Food and Drug Administration who advise that pregnant women and children completely avoid these fish with higher levels of mercury.
As for how much to eat, from the NOAA Fisheries site, I found that the U.S. Department of Agriculture (USDA) 2011 Dietary Guidelines for Americans recommends that we consume around 3 to 6 ounces of fish twice each week. WebMD seems to indicate that even pregnant women and children can eat up to 12 ounces of fish each week.
My plan when it comes to eating fish
Fortunately, I tend to enjoy eating fish about once a week, and a six ounce serving is about the right amount for me and each family member. Plus, we love wild salmon, which is a low-mercury, highly nutritious fish. Given that I have children, eating salmon or other low mercury fish once a week seems like a safe approach to take while still regularly getting the benefits of fish.