Study: Eggs From Free-Range Hens Have More Fat And Pollutants Than Eggs From Conventional Hens

FreeRangeEggs2Are eggs from free-range hens healthier than eggs from industrially-raised hens? It depends on how you define “healthy.” This study found that free-range eggs contain more fat and about the same amount of cholesterol. Eggs from chickens that are allowed to roam free may also have higher levels of dioxins, PCBs, pesticides, and heavy metals. By these data, free-range eggs aren’t any healthier and may in fact be less healthy.

Comparison Of Fatty Acid, Cholesterol, And Vitamin A And E Composition In Eggs From Hens Housed In Conventional Cage And Range Production Facilities, Poultry Science, 2011

The public perceives that the nutritional quality of eggs produced as free range is superior to that of eggs produced in cages. Therefore, this study compared the nutrient content of free-range vs. cage-produced shell eggs by examining the effects of the laboratory, production environment, and hen age.

Eggs from the range production environment had more total fat (P < 0.05), monounsaturated fat (P < 0.05), and polyunsaturated fat (P < 0.001) than eggs produced by caged hens.

Although range production did not influence the cholesterol level in the egg, there was an increase in fat levels in eggs produced on the range.

Eggs from free-range chickens have been measured to have higher levels of dioxins, PCBs, pesticides, lead, mercury, and other heavy metals than conventional eggs. This is primarily a result of environmental pollution which contaminates soil – everywhere, even in rural areas – which persists (that is, does not break down), and which bioaccumulates:

On a positive note, arsenic-laced feed is no longer fed to commercially-raised chickens (FDA to Withdraw Approvals of Arsenic in Animal Feed), so meat and eggs from chickens should contain less arsenic. It also means that poultry manure and litter should contain less arsenic. That litter is used as fertilizer for crops, even organic crops. It is why arsenic levels in rice are so high. (Hormone use in poultry production is illegal.)

7 thoughts on “Study: Eggs From Free-Range Hens Have More Fat And Pollutants Than Eggs From Conventional Hens

  1. Anrosh

    A longitudinal study would have been interesting in this case . Dont you think ?

    Let me given you an example : Because of the newly erected telephone lines for Mobiles, Coconut trees are producing smaller coconuts – I dont have a study to prove it. The farmers in Kerala ( southern tip of india where coconut trees are its local vegetation) was mentioning this .

    We need farmers , NOT PHARMers


    1. Bix Post author

      I do think that pollution, all types of pollution, is having a negative impact on our food. Here again, as in so many matters, it’s the consumer against big business.


  2. Bix Post author

    I wonder about endocrine disrupters. Just as humans need to be careful not ingesting, say, BPA in can linings and plastic bottles, so chickens need to be careful, for their own sake surely, and for the sake of those who eat them. If I saw a piece of plastic in my food, I wouldn’t eat it. Would a chicken? Would a chicken not eat a grub that was exposed to plastic?

    I think grazing pastures for free-range birds need to be clean, no pressure-treated wood, no RoundUp used in the soil for years, or blowing in from the neighbor, no trash. You’d have to pick up plastic, painted items, aluminum foil and other bits of metal that might have blown in after a storm. The bigger the pasture, the bigger the job. At least in a factory setting you have more control over what they eat. But you have other problems … high density invites pecking attacks (which is why their beaks are cut off) and infection.

    There’s another whole issue of the male chicks. Where do they go? Even on a free-range, organic farm.


  3. Melinda

    Male chicks become meat. But I would never eat eggs from cage-raised animals–the issues you mention (pecking, etc) are part of it, but there are larger aspects to the cruelty involved in that method of obtaining eggs. Plus the caged chickens are fed with things chickens weren’t meant to eat, like corn & soy (probably GMO, as about 89% of corn in this country is genetically engineered).


  4. Bix Post author

    I was under the impression that the male chicks were not used for meat, but were fed into a grinder while still alive and discarded. I read that they used to be tossed into a plastic trash bag and smothered but that was thought too inhumane.

    “Chick culling is the process of killing newly hatched poultry for which the industry has no use. Due to modern selective breeding, laying hen strains differ from meat production strains. As male birds of the laying strain do not lay eggs and are not suitable for meat production, they are generally killed soon after they hatch[1] and shortly after being sexed. Methods of culling include cervical dislocation, asphyxiation by carbon dioxide and maceration using a high speed grinder”
    Chick Culling


    1. Melinda

      I know small farms where male chicks are sold for meat once they’re a bit older. The farmer may keep one or two as roosters if they’re going for fertilized eggs. But the thought of grinding them up alive is just appalling! I’ve never heard that, but I don’t doubt you’re right. Humans are so cruel and so lacking in empathy. Plus it’s wasteful (to throw away potential meat) in a world where we have maybe 60 more harvest-years b/c of the despoliation of the soil by agri-biz. (Did I provide a link previously about the ruination of our soil?) And I totally agree with you that fields *should* be immaculately kept. But how likely is that to happen? Oy. Oh, one other thought–it’s very difficult, still, to find BPA-free can linings. Do you think that’s rather a class issue (like organic food)?



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