Sustainable Health Nutshell: Treat fish as a treat- eat it at most 1-2 times a week, and to keep fishermen in business, the oceans full of fish, and yourself healthiest, choose your seafood carefully from the Seafood Watch guide every time!
I realize I’m pole-vaulting over the topic of the health of the oceans in general, but for today, I’m covering two important things: 1. The seafood we eat is animal muscle and therefore susceptible to the things discussed in The Meat Issue, and 2. Increased popularity and marketing of seafood as a “healthy” alternative to “meat” has decimated fish stocks (see this great article) and the commercial fishing industry’s unrestrained harvesting to take advantage of the popularity has hurt small fishermen’s livelihoods. This is an unsustainable situation for more than just our (the U.S.’s) new seafood cravings. First, though, I’ll list the best choices to eat and not to eat in case you’re strapped for time.
Healthiest options for you and the ocean: wild-caught Alaskan salmon, Pacific sardines, farmed oysters and mussels, troll or pole-caught albacore tuna from B.C. or US, wild-caught Dungeness crab from US west coast, wild-caught Atlantic longfin squid, and tank-farmed rainbow trout, barramundi, and Arctic char. Check this great company for fish they’ll ship to you and info about their sustainable practices! No, I’m not paid for advertising for them. Yet.
Please don’t buy or eat these!: Farmed salmon, orange roughy, sharks, Chilean seabass, grouper, and most imported seafood including shrimp, swordfish, and mahi mahi. Tuna is difficult because of the popularity and processing issues involved- check where and how it’s caught- this page is helpful but still confusing- and at least avoid tuna caught by long-line and purse-seine (the most commonly used type of fishing gear), and avoid the bluefin variety entirely. Oh. And NEVER eat GMO seafood like the salmon that bypassed any safety studies at all…
Now this may seem obvious but here it is: the animals we consider ‘seafood’ and fish are animals. We often forget this since we’re land creatures ourselves and more used to categorizing animals as things that walk or fly. A huge number of vegetarians even consider fish not to be ‘meat’ and eat it along with dairy and vegetables (sometimes eggs are included there too). But in the realms of ecology and physical health, since most animals that are considered seafood consume plants and concentrate the plant energy into their more mobile forms, animal protein from the ocean must also be considered “meat.” (and for the remainder of the post I’ll say fish instead of seafood because really I’m too lazy to deal with grammatical/language issues involved there!)
Ok, so at different stages in the ocean’s food chain (sizes of fish basically), there are differences in the issues of sustainability of each population, scarcity in general of each species, concentration of pollutants and heavy metals in each fish caught, as well as differing percentage of omega-3 fatty acids and healthy nutrients like calcium and vitamin D in each species (which also depends on their diet- especially regarding farmed fish). The bigger and older the fish, the more plants and/or smaller fish it has eaten, the more energy and ‘extras’ (for instance, mercury, pesticides from runoff, plastics and its hormone-mimicking chemicals etc) will be concentrated into its body. [For articles on ocean plastic and the animals that eat it check this and this out.] For a more readily accessible correlation, you can think of the difference between a cow and a chicken (in terms of how much they have to eat to grow that size and how long their natural life spans are) being similar to a tuna and a tilapia.
One of the latest nutrition fads that’s caused a huge surge in fish consumption is the issue of omega-3 fatty acids, which is actually not super straightforward. The “American diet” involves way too many omega 6 and 9 fats, and not enough omega 3s, which our bodies can’t make for themselves even from the other types of omegas. Some fish can be a great source of these ‘good’ fats, and so have been promoted extensively recently, even to the point of popularizing taking supplements of fish oil. The thing is, just like any other ‘single nutrient,’ omega 3s haven’t worked as well as eating actual fish (and not fried fish!) as far as general health benefits. It may be an issue of oxidation (fried fish increase heart disease and stroke likely for that reason, but also most fish oil is purified by distilling up to 450 degrees F which, while removing mercury etc, would also cause significant oxidization), or an issue of the type of fish from which the oil is obtained (for instance, whale or seal blubber is a common source of ‘fish oil’ according to WebMD! that is not ok. they are also not fish.), or really, and more likely, as with most single nutrients our western ‘health science’ tends to focus on, that the whole food itself (in moderation) is the best way to obtain its health benefits!
So what are these benefits? Well, it’s still fuzzy too. One study by JAMA says overall mortality is 17% lower in fish-eaters. In an IOM study, for pregnant women, fish seem to promote healthy vision and brain development and prevent pre-term low birth-weight babies. (see the old summary article from the Washington Post here.) The most recent searches on UpToDate and WebMD list definite reductions in triglycerides, less chance of death from coronary artery disease, and then they get more vague. Maybe more fish (but not fried fish or fish cooked at high temperatures) or maybe more fish oil means less chance of atrial fibrillation, artery disease in general, osteoporosis, and inflammation, a slight reduction in blood pressure, and it might be helpful for some psychiatric and neurologic illnesses.
Honestly? It’s like any other animal. Raising pastured chicken and cows and such increases their amounts of omega 3s and nutrition profiles compared to corn-fed animals. Feeding corn to salmon or any other fish (yes, they do that in fish farms. it’s insane.) increases their ratio of ‘bad’ fats and makes them sick just like it does in cows (should we discuss antibiotics again? eh, nah. maybe read the eggs post again if you like. they have to do it to farmed fish too). Eating less animal protein (as compared to the typical American diet which includes meat in 2-3 meals per day) in general is better for you. Replacing corn-fed animal products with pastured animals, or with sustainable fish a couple times a week will likely improve your overall health. Cutting down to eating animal protein twice a week (or less, if at all) will very likely help you lose weight, improve your blood pressure and cholesterol, and reduce overall body inflammation and susceptibility to disease.
Paying attention to how the animals you eat grow up, including making sure their habitats are healthy (i.e. free of pesticides, fertilizers, and human waste like plastic!), and eating moderate amounts of locally caught/produced and sustainably caught/produced food from someone you actually know will help ensure the next generations grow up healthy and also that they’ll know how very tasty fish is. And doing these simple sustainably healthy things might allow you the chance to get to know those next generations, and to know them in a cleaner and more peaceful environment!