Who wants some eggs?! The answer is: a lot of us…on average, each American eats about 250 eggs a year.1 There are around 340 million egg-laying chickens in the United States2 and 5 billion worldwide.3 That’s almost equal to the number of human beings!
Why so many eggs? Because the egg really is incredible. We figured that out about 10,000 years ago when people first domesticated chickens in Vietnam.4 Eggs contain every essential vitamin and mineral that humans need, except for vitamin C.5 They’re also an excellent source of protein, which helps protect against bone loss6, and carotenoids, which lower the risk of heart disease and loss of eyesight.7 Although the cholesterol-laden yolk has attracted controversy, recent findings suggest that dietary cholesterol has little impact on blood levels of cholesterol.5 And, of course, eggs are simply delicious. Scrambled, fried, hard boiled, poached, or whisked into a baked good, eggs are a staple of the hearty American breakfast.
Are eggs green? Dr. Seuss thinks so… But scholars disagree. One kilogram of egg protein requires almost as much land to produce as one kilogram of pork or chicken meat protein, according to a study published in Livestock Science this year.8 Egg production emits less greenhouse gasses than pork, more than milk, and about the same as chicken. So eating eggs consumes just as much land and energy as eating meat. That alone might make a vegetarian go vegan.
However, 99 percent of Americans are not vegan!9 How can omnivores and vegetarians make their egg consumption greener? Are some eggs greener than others? Let’s look at the differences between conventional, cage-free, free range, organic, and pastured eggs. To unscramble the definitions of these egg labels, consult this click here.
Which egg is greenest? Some argue that conventional egg production is greenest because it’s most efficient. It’s true-conventional hens are more economical at converting the food they eat into food we eat. To produce one kilogram of eggs, a conventional chicken requires one kilogram of feed. Cage free, free range, and organic chickens all need at least 14 percent more feed to do the same.10 That’s partly because, unlike conventional chickens, they have room to waddle and flap their wings, which consumes energy. BUT, this doesn’t necessarily make conventional eggs the greenest.
Factory farms-which make conventional eggs and cage free, free range, and organic eggs-produce a great amount of waste, mostly in the form of manure and carcasses. Hatcheries kill all male chicks, which amounts to about 250 million dead chicks in the United States each year!11 Many factory chickens also die of suffocation, slaughter, disease, or drugs before going to slaughter. Their bodies are dumped in pits, “which become cesspools of bacteria, leaching into groundwater.”12 Every million hens produce about 125 tons of manure a day, and that too gets dumped.13 Of course, the half a billion eggs that were recalled for salmonella this summer from two Iowa farms also ended up in the trash…
The antibiotics that conventional, cage free, and free range chickens (i.e. non-organic egg producing chickens) routinely consume further pollute lands and waters. Of the 2.2 million pounds of the antibiotic arsenic compound Roxarsone that U.S. chicken producers use each year, more than 95 percent of it is excreted in chicken waste, which is sometimes applied to soil as fertilizer. The compound pollutes water supplies and may transform into a cancer-causing inorganic form of arsenic.14
Factory-farmed eggs also burn tons of gas miles to get to your plate. Most eggs in the United States come from Iowa, Ohio, Pennsylvania, Indiana and Texas.1 For more on “Food Miles” check out this GreeniacArticle. Since organic eggs contain less antibiotics, fertilizers and pesticides, you might conclude that they’re the greenest of factory-farmed eggs. If you prove that efficiency is more important than pollution, you might build a case for conventional eggs too.
But there’s a greener alternative—pastured eggs come from chickens that roam outside and supplement their feed with living grasses. On well-maintained small farms, chickens are integrated into an ecosystem that minimizes waste. Their composted manure fertilizes the soil, and their predilection for pecking bugs out of cow patties reduces insect populations, thereby minimizing pesticide use. If you buy pastured eggs from the market or farm, you might even avoid the Styrofoam or paperboard cartons. Unfortunately, pastured eggs still aren’t available everywhere. If you have to drive 30 miles to buy them at your nearest farm stand, is that green? Moreover, the term “pasture-raised” isn’t regulated by the government.15 Unless you’ve met the farmer, you won’t know whether you bought an eco-friendly dozen or just a green-washed phrase.
Thinking about going vegan now? If you’re not ready to go cold turkey, try cutting your egg consumption in half, or reduce just one egg at a time!
