You see grass-fed beef at your grocery store, and while it might sound self-explanatory, you’re still not entirely sure what that means for your health. So, what is a cow’s natural diet? Does the way cows are fed alter the nutrient composition of their beef? What are the pros and cons for someone on a keto diet? Let’s compare grass-fed vs. grain-fed beef.
What Does Grass-Fed Mean?
Throughout evolution and especially pre-agriculture, people consumed animals that were free-roaming and ate grass. Studies show the nutrients in beef vary depending on the cow’s diet.
Grass-fed beef means the cow was fed their natural diet of grass for at least part of their life. Grass-fed beef can be used to refer to cows that were raised on grass, then had their diet supplemented with grain or were switched to a grain diet to fatten up. “Grass-finished” generally means that the cows were never fed grain. Many grass-fed beef products are also antibiotic-free, meaning the farmer or rancher has also chosen not to use antibiotics.
What Does Grain-Fed Mean?
Grains are essentially the seeds of grasses. In feedlots and modern mass-producing meat operations, cows are fed large amounts of refined, processed grains.
In the United States, calves are allowed to roam free and eat grass for the first 7-9 months or until they reach 650-750 pounds. After that, most conventionally raised cows are transported to feedlots, in which the cows are placed in confined stalls.
The different feeding practices vary, but the cows are usually quickly fattened up using refined grain-based feeds that are often sprayed with pesticides and derived from a base of corn or soy. Fattening them up quickly in this way also helps produce the intramuscular marbling many customers desire.
The diet of grain-fed cows is often supplemented with minor amounts of dried grass, and they are often given growth hormones and antibiotics to increase growth. They’re also given antibiotics because the unnatural diet makes them more prone to illness.
To reduce dependence on antibiotics and combat the rise of antibiotic-resistant bacteria, the U.S. Food and Drug Administration (FDA) passed the Veterinary Feed Directive legislation on January 1st, 2017, stating that antibiotics deemed important in human medicine can’t be used for growth promotion and must be administered under the oversight of a licensed veterinarian. 
Grass-Fed Vs. Grain-Fed Beef: What’s the Difference?
To keep it simple, grain-fed cows eat mostly an unnatural diet of refined soy and corn during later life. Grass-fed cows eat mostly grass. There might be a slight difference in the taste and texture of the meat.
Differences in Fatty Acid Composition and Calories
Grass-fed beef typically has less total fat than grain-fed beef, and grass-fed beef also contains fewer calories, which could be helpful for those counting calories on a keto diet. The cut and breed of meat also affect the fatty acid composition.
Compared to grain-fed beef, grass-fed beef contains up to five times more healthy omega-3 fats and around twice as much conjugated linoleic acid (CLA). CLA might be protective against metastatic breast tumors. For example, in one animal study, fairly low levels of CLA were needed to suppress mammary tumor growth. CLA is concentrated in the fat, so fattier meats will have more than leaner meats.
Grain- and grass-fed beef have similar amounts of omega-6 fatty acids, and grass-fed beef contains less monounsaturated fat than grain-fed beef.
More Nutrition in Grass-Fed Beef
Grain- and grass-fed beef both provide important health-boosting nutrients like vitamins B12, B3, B6, C, and K2, as well as selenium, zinc, and iron. Beef of any kind contains carnosine, creatine, and high-quality protein, which is crucial for your brain and for building muscle.
The winner on the nutrition front is grass-fed or grass-finished beef, which is higher in certain nutrients, such as:
Vitamin E: An important vitamin for reproduction and vision health and an antioxidant that protects cells from oxidation.
Vitamin A: Grass-fed beef provides carotenoid precursors to vitamin A, including beta carotene, which is known to protect vision. Remember vitamins A, D, E, and K are fat-soluble and largely stored in the fat of the animal.
Cattle that graze and roam freely can increase the carbon-carrying capacity of the soil and restore crucial nutrients to depleted soil. Properly raised cows have a minimal negative effect on the environment and can actually improve the environment.
Proponents of grass-fed beef point out that monoculture crops, such as corn and soybeans grown to feed grain-fed cattle, destroy topsoil and increase greenhouse gasses in the atmosphere. On the other hand, they believe naturally grazed cattle can help the soil sequester more carbon and offset greenhouse gas emissions. In other words, eating natural grass-fed organic beef and supporting regenerative agriculture can actually assist in reducing carbon in the atmosphere.
Regenerative agriculture is backed by decades of research and designed to mimic nature with the goal of rebuilding organic matter and healthy soils and restoring degraded soil biodiversity, fertility, and nutrient density. This way of agriculture also increases water retention and promotes cleaner and safer water runoff, as well as boosting local economies with family farming and preserving traditional indigenous farming practices. Locally grown produce also generally has a lower carbon footprint. 
What About Organic?
Organic is a label that means the cow was raised on certified organic land without synthetic pesticides, GMOs (genetically modified foods), or fertilizers. The organic certification also means the cows must be fed a diet free of antibiotics and hormones and have outdoor access to graze in the sunshine on a pasture all year round.
Organic cows are considered healthier. Remember, organic doesn’t necessarily mean grass-fed, and grass-fed doesn’t necessarily mean organic, so it’s helpful to look for both labels if you’re interested in consuming beef that was both organic pasture-raised and grass-fed. The USDA (United States Department of Agriculture) Agricultural Marketing Service must certify the meat for it to be labeled organic.
Grass-Fed or Grain-Fed Beef? The Final Tally
Now that we’ve looked at some of the research around grass-fed and grain-fed beef, here are some points to consider:
Remember not to overcook your beef, which can cause potentially harmful compounds to form.
Grass-fed or grass-finished beef is often more expensive, so it’s up to you if you believe it’s worth the extra cost and if you’re able to or want to vote with your dollar to ensure cows are raised more humanely.
Grass-fed beef has more beneficial omega-3 fatty acids and CLA.
Herbs and grasses are a more natural diet for cows than processed soy or corn.
Lots of people go grass-fed and organic for ethical reasons because cows living in their natural environment eating their natural diet are healthier and happier.
Grass-fed and pasture-raised cows exercise more and roam freely.
Grass-fed beef is becoming more widely available, though in some places, it might be inconvenient or even unavailable.
Grain-fed beef is still nutritious and usually much more affordable, so don’t worry if you can’t always afford or get access to grass-fed beef.
Steph Green is a writer, researcher, and singer/songwriter with a passion for all things wellness. In 2016, after four years of struggling with her own health problems and painful autoimmune disease, Steph developed a life-changing and extensive knowledge of keto, nutrition, and natural medicine. She continues on her healing journey and enjoys helping others along the way.
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