Farmed tilapia is promoted as good for your health and for the environment at a time when many marine stocks have been seriously depleted. But tilapia has both nutritional and environmental drawbacks.
Compared with other fish, farmed tilapia contains relatively small amounts of beneficial omega-3 fatty acids, the fish oils that are the main reasons doctors recommend eating fish frequently; salmon has more than 10 times the amount of tilapia. Also, farmed tilapia contains a less healthful mix of fatty acids because the fish are fed corn and soy instead of lake plants and algae, the diet of wild tilapia. In farmed tilapia, raised largely on corn and soy, omega-3 levels depend on how much fish meal or fish oil the farm’s breeders mix in. While most fish species need a good helping of these fatty acids to grow, herbivorous tilapia grow decently with little or none. And there are compelling reasons to skimp on fish meal or oil additives: they are costly and create more pollution.
Environmentalists argue that intensive and unregulated tilapia farming is damaging ecosystems in poor countries with practices generally prohibited in the United States — like breeding huge numbers of fish in cages in natural lakes, where fish waste pollutes the water. “We wouldn’t allow tilapia to be farmed in the United States the way they are farmed here, so why are we willing to eat them?” said Dr. Jeffrey McCrary, an American fish biologist who works in Nicaragua. “We are exporting the environmental damage caused by our appetites.”
Fish farms may not use prophylactic antibiotics. But even the new rules allow for some practices considered unacceptable in the United States, where cage farming in lakes is generally forbidden. In many states, tilapia must be housed in specially designed pens with roofs to prevent birds from carrying the fish elsewhere; their waste is often collected to use as fertilizer rather than released. Also, the new standards allow for baby fish to be fedtestosterone even though markets like Whole Foods will not buy hormone-treated seafood.
Source: NYTimes.com
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