Advice for eaters of swimming water creatures.
Hi folks, and welcome to another Make-it-Green Girl's Quick and Dirty Tips for an Earth Friendly Life. Today I'm going to talk about fish -- how to pick environmentally friendly fish that's better for you, the fish, and the ecosystem.
OK, so in episode number 22, The Carnivore's Dilemma, I told you guys to cut down your meat consumption -- to zero if you can -- to ease humanity's load on the environment. I have to say that I think fish eating is on the list of no no's for eco-nerds, too. The reasons are less obvious, so I'll go over them one by one so you can pick your battles. And really, that's the only way any of us are going to survive the tremendous amount of information we have to learn just to get a decent meal that's good for us and the earth.
For nutritional information, I turn to the experts. The Nutrition Diva has all sorts of good information on healthy eating, so let's hear what she has to say about the health benefits of fish.
This is Monica Reinagel, the Nutrition Diva. Thanks, Make it Green Girl, for having me on the show today. Fish are a good source of protein and they're low in saturated fat, so many people see see fish as a healthier alternative to meat. But the primary health benefit you get from eating fish is that they are high in omega-3 fatty acids. Omega-3s are healthy fats that protect your heart and brain. The omega-3 fats found in fish can help lower your blood pressure, cholesterol, and triglycerides, and may protect against Alzheimer's disease, too. Because omega 3s are anti-inflammatory, they've also been found to help with things like arthritis, asthma, and irritable bowel syndrome.
Fish that are especially high in omega-3s include salmon, herring, mackerel, and sardines.
Thanks Nutrition Diva!
OK, not to burst that bubble folks, but if you want these health benefits, you have to do it carefully. We've discovered that aquatic habitats tend to concentrate toxins because the food chain is very long. Whereas on land, the sun nourishes grass which nourishes cows; in the water, your tuna may have eaten another fish that ate a smaller fish that ate yet smaller fish, eventually down to the microorganisms swimming in the water.
Mercury emissions from coal-fired power plants settle on the land and quickly leach into the water where bacteria attach it to a methane molecule, turning it into methylmercury, which is far more dangerous to you than elemental mercury. Methylmercury is a neurotoxin that is taken up readily by your tissues and stored in your body, whereas inhaled exposure to mercury from a broken thermometer or light bulb is easier for your body to clear out. For more in depth information about that kind of mercury exposure, check out Make-it-Green Girl number three, CFL Safety.
The higher up the food chain your fish is, the more methylmercury it contains. So when you are choosing fish, generally those species that have eaten relatively few lower-order fish are the safer ones. A seafood card you can carry with you to the store and restaurants can inform your choices by telling you which fish tend to be higher in mercury, but keep in mind it's no guarantee. No one tests for mercury in fish because (a) it would be ridiculously expensive, and (b) it's not required by the FDA. There are links to the seafood card at the end of this transcript at the Make-It-Green Girl section of QuickandDirtyTips.com.
Methylmercury exposure is specifically dangerous for pregnant women because it can cross the placenta and expose the fetus to disproportionately high levels.
Fish Farms and PCBs
Another reason environmentalists stay away from fish is that stocks all over the world are collapsing. Fish are not breeding as fast as we can hunt them, especially with the invention of huge industrial trawlers. There is yet another seafood card for you wallet to let you know which of these are at the most risk for collapse or are sustainably caught. Unsustainable fishing practice includes high by-catch methods like indiscriminate netting.
One of industries' answers to the overfishing problems is to start raising fish in farms. The aquaculture industry has expanded rapidly into markets all over the world and has quickly risen to the level of the agriculture business in terms of consumption of resources and pollution of local watersheds. Nitrate pollution, waste products, and antibiotics spill out of farms into waterways, and the farms themselves consume fertilizers, antibiotics, and corn-based food stocks just like industrial animal farms.
Health dangers from farmed fish again come from concentration of toxins. Polychlorinated biphenyls or PCBs are poisonous organic molecules that slide up the food chain because they are deposited into the fatty tissue of the fish. The fattier the fish, or the higher up the food chain, the more PCBs are stored in its tissue. They're also very persistent in human bodies, especially in women. PCBs don't just affect industrial countries either -- high concentrations of PCBs have been found in Inuit mother's breast milk because they have a high concentration of seal fat in their diets.
So you have some options out there, and some resources to help you make sense of it all. Unfortunately, the burden is now on us as consumers to avoid tainted fish. Minimize your risk and protect fish populations by using your seafood cards. If you want to eliminate your risk altogether, which you should definitely do if you are pregnant or nursing, you must stop eating fish altogether. Here's some good advice from the Nutrition Diva:
If you'd rather not eat fish, you can get omega 3s from vegetarian sources as well. Walnuts and flaxseeds are both high in omega-3 fats--although not exactly the same form that you get from fish. You can also find supplements that have the same form of omega-3 fats that you get from fish, only they are derived from algae instead. Either way, you want to be sure you're getting your omega-3s.
In short, make sure you know what you're getting, because the government and industry sure won't do it for you.
What to Eat by Marion Nestle
Co-op America article on Safe Seafood
Seafood Wallet Card - Sustainability
Seafood Wallet Card - Mercury and PCBs