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Grass-Fed vs. Conventional Meat: It’s Not Black or White


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This article is part of a special report on Red Meat. To see the other articles in this series, click here.

I hope you all had happy holidays and are off to a great start this year. I thought I’d share a few thoughts that have been bouncing around my head lately, stimulated most recently by two articles written by fellow health bloggers.

Don Matesz over at Primal Wisdom wrote a thought-provoking piece on the hormone composition of grass-fed and factory-farmed meat. In it he argues (convincingly, I might add) that meat from CAFO (confined animal feeding operations) does not have dangerously high levels of hormones, in spite of claims to the contrary made by advocates of eating grass-fed meat.

Got testicles?

I recommend reading the entire article, I’ll summarize it briefly here. Before CAFO came into being, humans predominantly ate bulls, since eating female animals (cows) was taboo. The taboo made perfect sense in a hunter-gatherer culture, since killing the female could eliminate potential offspring, while killing a few bulls would have no effect on the fecundity of the herd.

Today, CAFO use steer, which are neutered bulls. One reason for this is that steer are a lot easier to manage than bulls. Why? Because hormone levels in bulls (with intact sex organs) are significantly higher than in steer. In fact, bull meat has between 34 and 105 times more testosterone than steer meat. No wonder bulls are harder to manage!

Even when hormones are added to steer in CAFO, the levels are nowhere close to what they are in intact bulls. In fact, studies have found no significant difference in hormone levels between meat from hormone-treated and untreated animals.

This means that Paleo Pete was eating meat with a lot more hormones in it a million years ago than American Andy is when he gets a cheeseburger at McDonalds today.

Hormones in meat are bad – if you eat 200 pounds of meat a day

Studies have also shown that the hormones ingested from food, including CAFO meat, have a negligible effect on human health. From Don’s article:

For example, a prepubertal boy, most vulnerable to adverse effects of excess dietary estrogens, produces about 100 micrograms of estrogen daily. Beef muscle meat contains less than 0.02 micrograms of estrogens per kilogram. To get from beef an intake of estrogens equal to just one percent of his endogenous estrogen production, i.e. 1 microgram, he would have to consume 50 kilograms–110 pounds– of beef in a day!

Another common claim is that adding hormones to meat has increased the rates of cancer and other modern, degenerative diseases. But if that were true, we would have seen these diseases in hunter-gatherer populations that were eating large amounts of bull meat, which has on average 50 times more hormones than the CAFO steer meat eaten today.

So it would seem that there isn’t much difference between grass-fed and CAFO meat when it comes to hormones. So should we all just save some money and eat conventional meat?

It’s not all about hormones. Don’t forget omega-3s!

Not so fast. Mark Sisson published an article earlier this week reporting on a study comparing the effects of eating grass-fed and CAFO meat on omega-3 and omega-6 concentration in human plasma and platelets.

Turns out those that ate the grass-fed meat had significantly higher levels of omega-3 in their plasma and platelets than those that ate CAFO meat, despite the fact that the amount of omega-3 fatty acids in the two types of meat were not hugely different.

The folks consuming grass-finished meat ate, on average, 65 mg/d of long chain omega-3s, while those eating concentrate-finished meat ate about 44 mg/d of long chain omega-6s, yet the lab results – the big improvements in plasma and platelet fatty acid numbers – were lopsided.

What’s happening here? I suspect the answer lies with the difference in omega-6 content in the diets of both groups. Those who ate the CAFO meat had an average intake of 8.5g/d of omega-6 fats, while those that ate grass-fed meat had an average intake of 5.5g/d. In a previous article about how too much omega-6 is making us sick, I explained that omega-6 and omega-3 fatty acids compete for the same conversion enzymes.

Several studies have shown that the biological availability and activity of n-6 fatty acids are inversely related to the concentration of of n-3 fatty acids in tissue. Studies have also shown that greater composition of EPA & DHA in membranes reduces the availability of AA for eicosanoid production.

This works the other way, too. The more omega-6 is consumed, the less omega-3 is available to the tissues. So if two people eat a diet identical in omega-3 content, but one person’s diet is high in omega-6, and the other persons is low, guess who will end up with more omega-3 in their tissues? That’s right – the one with a low omega-6 intake.

This is why I constantly tell people that the most important step they can take in normalizing their omega-3:omega-6 ratio is not boosting omega-3 intake, but reducing omega-6. And this is likely what explains the higher levels of omega-3 in the grass-fed meat eaters in the study, even though grass-fed meat doesn’t have a lot more omega-3 than CAFO meat.

This is important because the ratio of omega-3 to omega-6 in our tissue is crucial to health. Too much omega-6 in relation to omega-3 has been shown to be a factor in everything from depression and arthritis to heart disease and diabetes. There isn’t a modern disease out there that isn’t influenced by this ratio.

Black, white & shades of grey

So here we have one study suggesting there isn’t much difference between CAFO and grass-fed meat, and another suggesting the opposite. What do we make of this?

As much as we’d all like things to be simple when it comes to food and health, they often aren’t. We have to use our brains to sift through the available information and make intelligent choices based on several different factors.

In the case of grass-fed vs. CAFO meat, there’s a lot more to consider than hormones and fatty acids. There’s also antibiotic use in CAFO cattle and the increased risk of foodborne illness in CAFO meat, and there are several economic and social issues as well.

Grass-fed animals are generally treated in a more humane way than CAFO animals. If you’ve ever visited a CAFO you will know what I mean. It’s shocking and disgusting. I personally prefer to support local farmers that use traditional methods of animal husbandry, that pay attention to how the animals are treated and slaughtered, and who care about every phase of the process. I like the money I spend on food to stay in my local community whenever possible. And if you’re looking for a different alternative, there are several benefits of using bone broth when cooking as well!

Clearly, this is not a black and white issue, and there’s a lot to take into account when choosing between grass-fed and CAFO meat. As usual, I’d love to hear your thoughts.

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Join the conversation

  1. This article seems to assume that “hormones are hormones” — that excess testosterone must be as bad for the body as excess estrogen, because they’re both hormones. This is just silly…. you might as well say that taking fish oil is just as bad for people as drinking motor oil, because they’re both oils.

    A more likely answer is that steer meat is bad for people BECAUSE the bulls have been neutered (turning them into steers). This makes sense, because neutering the cattle results in a higher estrogen to testosterone ratio (greatly lowered testosterone). In paleo days, this ratio was reversed.

    Add to this the synthetic hormones (estrogens again) used to fatten up the cattle nowadays, and the fact that “factory farm” cattle are seen wallowing in their own feces, and it’s no wonder that CAFO “red meat” has gotten a bad rep… it’s garbage I wouldn’t want to eat. But there’s no evidence at all that red meat from small organic farms where the cows are primarily fed on grass, is bad for people. All of the studies about the “horrors of eating red meat” have been conducted on large populations consuming mainly the putrid “meat” manufactured by factory farms.

  2. Tips for tight budgets (a concern addressed in several comments below). Start small, as we did. Start with dairy products–milk, butter, cheese, etc. A local grocer may carry one or more of these. The price will be higher, but the dairy product will be less chemically laden. And that’s good for your health. If there’s no grass-fed available, start with organic. If, or when, you can afford to move on to produce, investigate which stores in your area carry some that are organically grown. Seasonally, locally grown produce at your spring, summer and fall farmers’ markets is often touted by growers as having been raised without chemicals. The idea here is to incorporate, item by item, what you can afford to purchase into your dietary. Each small change helps. Finally, there are multiple, and good, reasons for considering grass fed meats–many of which are discussed by others, below. Several commentaries address the idea of a “group buy” of properly raised, unadulterated meat(s). Consider convincing several others among your acquaintances to join with you (and use this website’s discussions, or others’, to convince them). Above all, don’t feel daunted by changes in your dietary: a dollar carefully spent here may be far less than the dollars spent there, in the future, on ill health. I speak from experience: our grandchildren did not reach puberty earlier than their genetics suggested, and I am alive today thanks to the infant-commerce of “organic farming” which showed up on the shelves of one of our little local stores in the Sixties. That’s when a single produce item cost six times what the sprayed item cost–we ate less, to be sure, of that item but we gained nutrients. And over time, health.

    • This topic is covered In Don Matezs paper. Contrary to bro science, real science suggests it’s the opposite. Animal products conventional or grassfed are the lowest toxin foods. This is most likely because unlike plants animals don’t accumulate toxins in their tissues as a defense mechanism but rather they have a liver that functions to neutralize toxins. Don references studies that show that 99. Something percent of toxins we take in that have to be neutralized by our livers are naturally occurring in the plant foods we eat. Organic can be even higher than conventional. A tiny amount of toxins we take in are other manmade substances.

      Causes a totally different perspective to know these facts. Very freeing if you ask me.

  3. Truth be known is most grain feed beef are both Grass and grain. This entire thing started by the beef industry and Ethanol. The best way to produce large beef producing cows and affordable way to bring them up on grass and grain. Today’s farmers can no longer afford the grain! because of the Ethanol demand. Their cows are smaller and less productive. To up the price they are promoting “Grass Fed” as if it is better for you. They point you to cows only fed on grains. Truth is only 5% of cows are only fed grains and most of those are test subjects.

  4. Surely testosterone is just one hormone. The issue is the other hormones that are being given which are these…

    * Three natural steroids (estradiol, testosterone, and progesterone), and

    * Three synthetic hormones (the estrogen compound zeranol, the androgen trenbolone acetate, and progestin melengestrol acetate).

  5. Its not just hormones people are concerned about. There are more available nutrients in grass fed vs. Grain fed that’s what makes it better. Grain fed cows are sick and dying, grass fed cows thrive. What meat would you rather eat.

    • Grain fed cattle are sick and dying is a comment that makes my skin crawl.. I raise cattle. Mine are always on grass. I STILL have to use antibiotics on occasion. There are calves that will catch pneumonia from dust, bulls that might get a lump on their face from a tooth infection, cows that might cut their foot and get an infection. I, along with many producers I live by, only use antibiotics when needed. To me, it would be a shame to watch them slowly die rather than helping them. I would also like to point out that I could keep an animal that was treated separate. The time and work involved in it will make your meat much more expensive. On a similar note, grass fed beef will be far more expensive. It takes a lot longer for them to finish growing on grass only. My point is simply that you can you can have meat anyway you want it, just be ready to pay.

      • My concerns with antibiotics is the unhealthful way I see cattle living in modern feedlots and dairy farms. They abound in the Texas Panhandle near where I live. I see cattle trudging in dung, standing on dung hills. You don’t see this with cattle on the open range or grazing in pasture lands. I am not saying this about all farmers, some do carry out sanitary measures. Use antibiotics where you must, but please not as a prophylaxis for unhealthful conditions.

  6. What about torturing the animals in CAFO operations? I’m most worried about that. Also who did these studies? Did they have connections to any biased lobbies? That’s important but I didn’t see that info i’d just see things that say “Some studies were done”. The 2nd to last paragraph is the most important part of this article. That’s the part people should be focused on even more than omega-3’s and whatnot

  7. One point I missed in all this, no one talks about the taste. When I taste and smell cooked hamburger from the grocery store it smells metallic and unnatural, terrible. When I smell beef from our farm it smells earthy and natural and is a pleasure to eat and sits well in my stomach.
    My price for beef is simply an average of 4 stores in the area. It sells out every year.

  8. From the USDA website:
    “Grass-fed animals receive a majority of their nutrients from grass throughout their life, while organic animals’ pasture diet may be supplemented with grain. Also USDA regulated, the grass-fed label does not limit the use of antibiotics, hormones, or pesticides. Meat products may be labeled as grass-fed organic.”

    “Federal regulations have never permitted hormones or steroids in poultry, pork, or goat.”


  9. I feel a lot more comfortable eating the natural produced-in-the-body hormones that Paleo Pete was having for dinner vs the man made growth hormones that American Andy has in his fast food burgers.

  10. Thanks for the information about the omega sixes and threes competing for the same enzyme, that is great information.

    I think however that antibiotics in the CAFO meat deserve more emphasis as a health detractor – I find commercial meat knocks down my internal flora bigtime.

    Roswell Chiropractor Dr. Georgia Herrera

  11. Grass Fed Natural Meats, Located in Massachusetts, 28 Corey Hill Road Ashburnham Ma 01430. Store hours, Weekends or by appointment. Great stock of meats, Beef, Pork, Lamb, Chicken and free range eggs. Raw honey and maple syrup

  12. Right from Canada Beef:


    “There is no such thing as hormone-free beef. Even beef raised organically will contain hormones.”

    Estrogen (nanograms) Progesterone (nanograms)

    Beef from cattle not given hormonal growth promotants 100g 1.5 27
    Beef from cattle given hormonal growth promotants 100g 2.2 44
    Milk, 250 mL 35.9 Not applicable

    There are quite a few more natural hormones in flesh. This information is quite disturbing and it doesn’t matter if it’s grass-fed or factory farmed animals, you’re still eating those hormones.

  13. Testosterone is not the only hormone, and not necessarily the one we are concerned about. What about synthetic growth hormones added to CAFO meats, the ones designed to make animals fatten up quicker?

  14. Great site and Info. However, I’m an out of work single mom who cannot afford to go miles out of town to buy costly grass fed meat. None of the local stores sell it. What is someone like me to do when trying to deal with autoimmune issues and eat healthy?

    • Consider splitting a cow’s purchase/a cowshare (part of a whole cow’s meat) with others nearby, and either transporting once or getting others to transport, a local CSA(also useful for produce), or purchasing bulk online from a company like U.S. Wellness Meats ($7 handling fee) or others selling pastured poultry and grass-fed meats and fats. Acquire adequate freezer space. Bulk buying of meat is often cheaper.

      Consume as much negligible-pesticide-level produce if organic produce is not an option as possible.

      Order saturated fats like grass-fed/pastured (e.g. Purity Farms) ghee or organic coconut oils and consume.

      Consume more seafood(wild-caught) — frozen is often quite cheap, make sure is either wild-caught or safe to eat farm-raised, like potentially oysters.  Mercury is supposedly not so much a concern with truly healthy gut flora and adequate selenium consumption (chelates mercury & renders inert), and high-mercury fish sometimes-to-often have high selenium (I think 1:5 selenium : mercury, but not sure if remembering correctly.)

      Heal your gut.

      Eliminate processed foods, gluten, potentially grains or starchy veggies, nightshades, pasteurized dairy (other than ghee), potentially raw dairy as well, and other things for at least a month’s period, then test sensitivity through gradual reintroduction like the Whole30.

      Read the Whole30 website for autoimmune protocol. Or the GAPS(Gut and Psychology Syndrome) Diet — both look quite useful for autoimmune problems. And effective.

      Take up a healthy, not necessarily high-strain practice of high-quality source material (not low, which is abundant) such as weight-bearing exercise, taichi, yoga, or pilates to help with overall internal organ , lymphatic , etc. health. Research into this more fully, as internal health will often heal external problems in a permanent way and create synergistic whole-body health, which is quite sustainable.)

      Buy spices and other foods in bulk. Replace cleaners, laundry detergents, washing soaps of any kind, with soap nuts (very versatile) or cheap homemade concoctions (also accessible from link). Replace paper towels and other disposable cloths (save for toilet paper, perhaps) with cloth napkins, which can be hand-washed or even machine-washed.

      Be happier. Be more fearless or fear- Pursue what makes you truly happy, and difficult (striving) goals which are what truly make you happy.

      Best of luck.

      Manjushri’s Sword

    • You can use your favorite search engine (google, Bing etc.) and enter “Where can I purchase pasture fed meat” then look at the results to see if anything suites your needs. If that doesn’t work for you, you can try looking into the site at http://www.eatwild.com/products/index.html and click the link “Shop for Local Grassfed Meat, Eggs & Dairy” a page with a map of the US will come up. Click on your state and a list of places in that state will come up. Look through it to find places that are close to you and check them out to see which ones have what you are looking for. You can also go to http://www.localharvest.org/ at the top of the page there’s a place for you to put in your city and state. Look thru the lists that comes up to see if anything comes up that interest you. You should be able to find what you are looking for on these sites. Another option is to find out where your local farmers markets are. There is a growing demand for local meat and produce. I live in a major city and there are lots of local farmers markets in my area. I don’t have lots of money for food as well. I have a food stamp budget without the food stamps. I thought this was going to be a problem for me too when I made the switch from conventional supermarkets for my food to healthier pastured meat and pesticide free produce. I’ll share with you what a cattle farmer at a local farmers market told me. He told me that the quantity I wasn’t able to afford I could make up for in quality, therefore needing less. Since the quality is better I didn’t need as much. He also told me that I could make quality soups and stews by starting with bone broth. There is lots of nutrients in bone broth (nutrient dense). Bone broth is made by getting quality animal bones and boiling them in water to make stock, either on a stove on a very low setting for 12 – 24 hours or using a crock pot on low and letting it cook for 12 – 24 hours. Since the stock is nutrient dense you don’t need as much meat and vegetable and you still have a very nutritious meal. Bones usually cost me about $2.00 -$3.00/lb. I generally use about 3 lbs of bones for 2 quarts of water. I make mine very concentrated. I then can it and get about 4 pint size jars out of it. I don’t have a lot of space to store it. When I am ready to use it I can make the pint of stock into 2 pints by adding a jar of water to the pot I just put the stock into. I then add the rest of the ingredients for what ever I’m making and let it simmer to bring the ingredients into a wonderfully delicious meal that didn’t cost a lot of money.