Eggs are quite possibly the world's perfect protein source. The six grams of protein in each egg has the highest biological value—a measure of how well it supports your body's protein needs—of any food, including beef. The yolks contain vitamin B12, deficiencies of which can cause attention, mood, and thinking problems.
Depending on where you're getting your eggs, though, you could be getting a lot more of stuff you don’t want. First you'll get some arsenic, added to feed to promote growth in hens but linked to various forms of cancer in people, and an extra dose of antibiotics, also used to promote growth but linked to antibiotic resistance and even obesity in people. Then add a heaping helping of salmonella. A 2010 study published in the journal Veterinary Record found that the eggs from hens confined to cages, as they often are in factory farms, had 7.77-times greater odds of harboring salmonella bacteria than eggs from non-caged hens.
You wouldn't know that based on what's starting to appear on egg cartons. Labels like "natural" and "cage-free" make eggs seem like they came from down on the farm, from chickens living happy lives and eating bugs. But that's not always the case. If all you want is healthy protein, it's time to start scrutinizing egg cartons. Following are nine of the most common egg-carton claims and what they mean for your health.
Here's how to make sense of the different egg labels:
What It Means: "Cage-free is certainly not like Old McDonald's farm," explains Paul Shapiro, spokesperson for the Humane Society of the United States. Generally, it means that animals are not kept in the tiny battery cages used in most egg operations. It doesn't mean the animals live outside or that they eat a diet free of arsenic and antibiotics. It is true that cage-free operations are slightly healthier for you. Cages generate more fecal dust, are associated with more disease-carrying rodents and insects, involve many cages that are difficult to disinfect, and lead to low natural immunity in stressed-out hens.
Can You Trust It? No. There's no independent third party that certifies egg producers as cage-free, so you really have to take producers at their word.
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Free-Range or Free-Roaming
What It Means: Usually these types of operations allow chickens outside of cages in barns or warehouses, but they aren't required to provide the animals any specific amount of time outside—or even exposure to sunlight indoors. Chickens can still be debeaked or forced into molting, a practice used to keep hens laying eggs for a longer period of time, usually accomplished by starving the chickens, according to the Humane Society.
Can You Trust It? No. Like "cage-free," there's no independent body that certifies hens as receiving adequate access to the outdoors, and the USDA has set no standards for using the claim on egg cartons.
Learn More: Avoid Supermarket Traps!
What It Means: A USDA-certified organic label means the eggs came from hens that were not enclosed in battery cages, and that must be offered access to the outdoors. But the amount and duration of outdoor access isn't well defined. Organic eggs come from hens that were fed certified-organic feed, free of things like arsenic and antibiotics, pesticides, animal byproducts, and genetically modified organisms (GMOs). Forced molting and debeaking are permitted in certified-organic production.
Can You Trust It? Yes. Egg producers are subject to annual audits of their operations and must pay a fee to be certified.
Read More: The 20 Best Organic Foods
What It Means: This means that the finished product hasn't undergone certain unnatural processes; in this case, that product is the egg.
Can You Trust It? NO! Neither the FDA nor the USDA have set any definitions for the word "natural" when it comes to eggs, and it's highly misleading. "Natural" eggs may have come from hens pumped up with antibiotics, fed feed containing arsenic or genetically modified corn or soy. And it certainly doesn't mean the chickens were raised in clean, humane conditions.
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What It Means: Pastured chickens are often housed on grassland in portable shelters that are periodically moved to give the chickens fresh pasture (and bugs!). Studies have shown chickens raised on pasture have twice the amount of vitamin E and more than 2.5 times more omega-3 fatty acid levels.
Can You Trust It? Only if you're buying from a farmer you know. There's no third-party inspection required to ensure that hens are roaming around a grassy pasture, but if you're buying eggs from a local farmer, you can ask him or her—or even see for yourself—how the animals are raised, what they're eating and whether they've been treated with antibiotics.
Read More: The Best Backyard Chickens
What It Means: Hens were fed feed with an increased amount of omega-3s, which may have come from flaxseeds, fish oil or algae. Technically, caged hens could also be fed flax feed, so don't equate this label with better living standards.
Can You Trust It? Sort of. You can always compare omega-3 claims with the Nutrition Info panel on the carton. Factory-farmed eggs naturally have about 50 milligrams and many "omega-3 enriched" eggs often have that same amount. So you're paying twice the price for regular eggs. Furthermore, there's no guarantee you're getting the beneficial EPA and DHA oils found in fish and algae. You could be getting ALA omega 3s from flaxseed, which are still healthy but not as beneficial. Finally, keep in mind that pastured eggs have twice the amount of beneficial omega-3s as factory-farmed eggs anyway, and the hens get to be outside.
Read More: The 15 Grossest Things You're Eating
Animal Welfare Approved
What It Means: The birds are cage-free and continuous outdoor access is required. They must be able to perform natural behaviors like nesting, perching, and dust bathing, and birds must be allowed to molt naturally. Beak cutting is also prohibited. Antibiotic use is allowed, but any animal that receives them has to be removed from egg-laying operations for an "antibiotic withdrawal" period. And though organic food isn't required, the program prohibits the use of animal byproducts, and encourages GMO-free food whenever possible.
Can You Trust It? Absolutely. A certification program of the independent, nonprofit Animal Welfare Institute, the Humane Society dubs this the highest animal welfare standard of any third-party auditing program. Farmers are subject to annual audits to ensure all standards are being met.
Read More: The 7 Best Eggs You're Not Eating
What It Means: Birds must be in cage-free environments and fed a diet free of animal byproducts and growth promoters, like antibiotics and arsenic. Antibiotic use is allowed to treat diseases but only under the supervision of a veterinarian. There's no requirement that animals have access to the outdoors but farmers do have to meet certain standards for space to perform natural behaviors, such as scratching and perching.
Can You Trust It? Yes. Though the standards aren't as stringent as Animal Welfare Approved certification, the certification is still administered by an independent third party (Humane Farm Animal Care) that subjects farmers to annual visits and requires diligent record-keeping.
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United Egg Producers Certified
What It Means: While forced molting is prohibited under this certification, debeaking is allowed, along with other cruel and inhumane practices, such as the use of battery cages. There are no guidelines for antibiotic use or any standards prohibiting animal byproducts or growth promoters in feed.
Can You Trust It? No. This is a third-party certification program, but the guidelines were developed by the food industry, not independent third parties. Shapiro says this, along with "natural," is one of the most misleading claims made on an egg carton. According to the Humane Society, the overwhelming majority of the U.S. egg industry complies with this program.
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Published on: August 24, 2010
Updated on: March 20, 2014