Are Free-Range Eggs Less Healthy Than Regular Eggs?

A new study may make sustainable foodies feel like they've got egg all over their faces. According to scientists at the National Cheng Kung University School of Medicine in Taiwan, free-range eggs are not as healthy as conventionally produced eggs.

Taiwanese scientists tested levels of pollutants in cage-free eggs and compared them to pollutant levels in regular eggs. According to their research, free-range eggs contained 5.7 times more dioxins and other environmental pollutants than conventionally produced eggs. Dioxins are hormone-disrupting toxins that can cause reproductive and developmental problems, immune system damage, and cancer. While most of people's dioxin exposure does come from food, it's definitely not an ingredient you want swimming around in your omelet.

But while this study examines a worthwhile topic, it fails to put the whole situation into context. Free-range chickens get to roam around outdoors, nibbling on plants and insects, so it makes sense that they might be exposed to more environmental pollutants than caged chickens, who spend their whole lives trapped inside. But the story doesn't stop there: Because free-range chickens get outside, some research shows that their eggs boast health benefits over conventional eggs. Mother Earth News conducted a study comparing free-range and traditional eggs. The publication found that cage-free eggs contained about one-third less cholesterol and one-quarter less saturated fat than regular eggs. Free-range eggs also boasted higher levels of omega-3 fatty acids, vitamin A, vitamin E, and beta carotene.

Chickens themselves benefit from free-range farming practices. According to the Humane Society, caged, factory-farmed chickens typically get about 67 square inches of space each. In other words, every bird gets an area about the size of a sheet of paper—hens can't even stretch their wings. Factory-farmed birds are practically living on top of each other, trapped inside their whole lives, and oftentimes fed a diet of corn, soy, and additives. Which chicken do you think is less likely to suffer from disease: A bird that's strutting around the Great Outdoors soaking up sunshine, or a chicken stuffed in a cage inside a warehouse packed with thousands of other hens?

It's also pretty ironic that this study found that free-range eggs contain higher levels of pollutants when factory-farmed chickens actually create a lot of the world's environmental devastation. Most caged chickens are fed resource-dependent grains, which take a ton of fossil fuels, groundwater, and topsoil to produce. Though more of a problem for cattle operations, factory farms also have a history of improperly disposing of waste and polluting waterways.

My point here is not to say that this study doesn't have any value—it does, and the health benefits and risks of various types of food is an area ripe for more research. But this study was quite small (scientists compared six free-range eggs to 12 regular eggs) and locally specific: Taiwan is an industrialized country with lots of incinerators. The fact that eggs contained dioxins isn't so surprising given how dirty the nation's air is. As I mentioned earlier, the study doesn't put the whole eggs picture into context, either.

If possible, the best way to buy eggs is to get them straight from a small, local farm. It's always better to know firsthand who produces the food we eat, and that way folks can see for themselves how a farm's chicken operations are run. As for me, I'm sticking with organic, free-range eggs.

Photo credit: Fir0002 via Wikimedia Commons