Paleo Diet – Why Grass-Fed?

FIGURE 1 (chart from














The Paleo Diet recommends that all protein sources should come from “grass-fed” animals.   “Grass-Fed” vs. “Grain-Fed”,  what’s the big deal?  You may be surprised to learn that grain-fed beef can be detrimental to your health.

I recently read an article in James Fitzgerald’s OPT on-line newsletterbyJeremy Gordon of CrossFit Hampton Roads.  Jeremy does an excellent job of not only sharing the ill-effect grain has on protein quality, but also on his own personal, self-enlightening journey into health and wellness.  Jeremy has kindly given fitfemaleforty permission to re-post his article below. written by

Grown-Up Thinking

Jeremy Gordon

One year ago, after viewing the movie, “Food, Inc.,” my family started a journey. This is a journey towards independence from an industrial food system. It is a journey vectored by critical thinking, fueled by a passion for wellness (self and earth) and the road is paved with “grown-up thinking.” (i) While we are still taking our first steps in this journey, the end-state (in my mind) is clear: we consume foods grown using sustainable, humane, local, organic methods; preferably raised by my family on our own property.

Two facts from Food, Inc hit home the most: the cruelty of Consolidated Animal Feeding Operations (CAFOs) aka Factory Farms, and the United States (and hence most western nations’) utterly blind worship and consumption of all things corn. And these two items are very closely related.

My journey took on a very aggressive tone; fueled by a sudden awareness of my total lack of control of the quality of my family’s food, and my blind contribution to a food system that in unsustainable and damaging to the world. I poured through books about the food system and I scoured the Internet on sites such as and the Weston A. Price Foundation. While reading Michael Pollan’s “Omnivore’s Dilemma,” I decided I needed to get off my ass and get my hands dirty.

(I apologize; I am just now getting to the point of this article. I’m passionate about this topic and I want no doubts as to my intentions in writing about it.)
The most troubling “grown-up” revelation I had was that the animal protein sources my family was eating (in general) were from CAFOs. This article discusses what I have learned about the impacts of feeding animals what they did not evolve to eat: the impacts on the animal and the subsequent impacts on humans who consume this meat. While I delved into poultry and swine while researching, I only address cattle in this article.

Grain Feeding Operations:   Feedlots and Grain Topping

Cows are herbivores. Their natural diet is simple: foraging on greens (grasses and legumes of all types). The purpose of a CAFOs is also simple: get cows fat as quickly and economically efficiently as possible. The art of feedlot operations is a balance between maximizing the growth rate of the cow while not killing it before it is ready for slaughter. In the commercial factory farming process, cattle are raised on ranches (eating their natural ruminant diet of forage) until the last 110-150 days (or so) of their approximately 14-month life. Their remaining months are spent in confined pens, laying in their own feces, eating a laboratory-created mixture of corn, urea (protein), silage, vitamin supplementation, generic “filler” mixture that includes waste from industrial human food production, animal byproducts from the slaughterhouse and a slurry of antibiotics to keep them alive. But grain feeding of cattle is not confined to only feedlot operations.

Many farms produce indigenous cattle through “grain topping.” Topping is similar to feedlots except the timeline (and hence the amount) of grain feeding is reduced, and conditions are generally better for the animals.

While conditions are generally better on private farms (vs. commercial feedlots), grain-feeding cattle affects their health regardless of the timeline. While shorter periods of grain exposure will limit the impacts, it is still introducing stressors and toxicity to the cow. Bottom line: introducing grain in the cow’s diet makes the cow ill and affects the quality of meat humans consume. Let’s look at some specific effects of grain on the cow’s health:


pH Balance in the Rumen

The cow’s digestive system is a marvel of evolution. A 4-chamber stomach takes grass, exposes it to bacterial digestion, and produces protein while transferring much of the vitamin and mineral content of the grass to the cow’s musculature and fat. This process primarily occurs in the rumen (a basketball-sized compartment), and relies on a delicate pH-balanced environment for the bacteria. The most critical impact to cattle during grain feeding is pushing the pH balance in the rumen towards acidity. This leads to a plethora of disorders that would eventually lead to (and often does lead to) the death of the cattle. The acid wears through the rumen (much as lectins irritate the human digestive tract), leading to abscessed livers. Upwards of 30% (and in some cases 70%) of cattle in a feedlot have abscessed livers at slaughter (ii). This necessitates feedlots to staff veterinarians—to keep the animals alive long enough to put on enough weight to be economically feasible at slaughter. Many of the other listed impacts are also a result of the damaged rumen. The acidic rumen is also blamed for the entrance of deadly E. Coli 0157:H7 into the human food chain (iii).

Altered Fatty Acid Composition

As shown in this chart (iv), this pretty picture (for those that don’t like staring at numbers), and this study The balance of Omega-3 (aka n-3) and Omega-6 (n-6) essential fatty acids (EFAs) is consistently skewed towards pro-inflammatory n-6 in grain-fed beef and towards anti-inflammatory n-3 in grass-fed beef. Skewed EFA balance in humans is a contributor to systemic inflammation and major contributing factor to diseases of civilization.   Loren Cordain, author of “The Paleo Diet,” places the human evolutionary n-6 : n-3 ratio between 2:1 and 4:1 and contends that consumption of grain-fed animals is a large contributor to skewed fatty acid balances in the modern western diet (skewed upwards of 30:1). The amount of time in which a cow is fed grain affects how much the fatty acid composition is skewed (ref Figure 1 “above”), but the drop off is rapid. Traditional grain-topped private farms feed their cows corn between 40 and 60 days prior to slaughter (vi). You can see there is still a dramatic shift in EFA composition in this time frame.

Conjugated Linoleic Acid (CLA)

CLA is a Polyunsaturated FA found in meat from ruminant animals (i.e. those with a rumen). Hence the name of its primary component: rumenic acid (vii). Studies show CLA plays an important role in lipid storage (insulin resistance..strangely enough), limiting carcinogenesis, and reducing atherosclerosis. CLA production relies heavily on rumen bacteria. The acidic rumen reduces bacteria activity and hence the CLA content of grain-fed meat compared to grass-fed meat. CLA content is generally touted as one of the most beneficial aspects of grass-fed meat.

Fat Soluble Vitamin Content

Vitamin A and Precursors

When cattle forage on grasses, they are ingesting carotenoids. Carotenoids (in particular ß-carotene) are precursors to Vitamin A: a fat soluble vitamin that is important for: “normal vision, bone growth, reproduction, cell division, and cell differentiation, maintaining the surface lining of the eyes and also the lining of the respiratory, urinary, and intestinal tracts, the overall integrity of skin and mucous membranes [and it creates] a barrier to bacterial and viral infection.”(viii) Vitamin A also plays a role in white blood cell production, thus making it a critical component to a healthy immune system. Grass-fed meat contains more than 7-times the amount of ß-carotene compared to grain-fed. This increased ß-carotene also causes a yellowish tint to grass-fed meat. Unfortunately, this is viewed as a negative property in the marketing of beef. Grain fed cattle is valued for its white “marbled” fat appearance.

Vitamin E and precursors

Vitamin E is a fat soluble vitamin with antioxidant properties. As with Vitamin A, grass-fed beef contains much more (3 times) the quantity of a -tocopherol (Vitamin E precursor). The nifty thing about this elevated a -tocopherol content is that the anti-oxidant properties of Vitamin E act to limit oxidation of the meat after the animal is slaughtered (ix). This means longer shelf-life and a brighter red color of the meat (you know what I’m talking about if you’ve ever had truly grass-fed meat).


The Choice is Yours

Just as OPT discusses the human “thermometer” of stress, our food sources have their own thermometers. When you take an animal designed to eat grass while roaming wild, and you pack it into a tight pen with a fecal-floor ripe with disease, and you feed it grain, antibiotics, industrial waste and animal byproducts, you are tipping the scales of stress. That animal is now ill. There are enough studies (ref. above) showing the negative impacts of grain feeding alone on fatty acid and vitamin composition. Now add to that the impact to the environment, the wellness of the animal and the downstream impact to the humans that consume grain-fed meat, and the choice is clear to me. Grain feeding cattle is a function of industry, not health and wellness. It is a convenient method of removing limitless quantities of corn from an endless, government subsidized supply. The “marbled” look of grain fed meat has been granted a higher grade and status by the same industrial architecture that removed cattle from the ranch and placed them into government subsidized feedlots with piles of exemptions from environmental laws (think runoff from millions of pounds of consolidated manure…this is how e-coli gets into spinach)(x).

What Can You Do?

The most powerful tool in my journey has been knowledge independent of what the Industrial Food System force-feeds us in the media. I have scoured the counter-culture of farmers who raise 100% grass-fed animals (Joel Salitin of Polyface Farms and Ted Slanker being the most outspoken). I made a field trip to a nearby farm andI asked the owner to set aside 5 cows for my gym to be 100% grassfed. I learned about their life cycle on the farm, I asked the deep questions and got answers from a 25-year cattle rancher. I’m starting my own path to independence from an industrial food system. I implore you to research local farms to find Pasture-raised animals and farms that use organic, sustainable methods (U.S, Canada). Grow your own food. Teach you children to do the same. Read The Omnivore’s Dilemma, watch Food, Inc. Whatever action you take to start your journey, do it with confidence and an open mind primed for Grown Up Thinking…you’ll be surprised where it takes you.

i A phrase used by author Lierre Keith in her outstanding book, “The Vegetarian Myth”
ii Pollan, Michael. The Omnivore’s Dilemma.
iii ibid
iv Daley et al. “Grass Fed Versus Grain Fed Beef: Fatty Acid Profiles, Antioxidant Content and Taste,” Nutrition Journal, 2010
v Simopoulos, “Omega-3 Fatty Acids in Inflammation and Autoimmune Diseases,” Journal of the American College of Nutrition.
vi Personal Interview: Pete, Owner of Windhaven Farms, Virginia
vii Nuernberg K, Nuernberg G, Ender K, Lorenz S, Winkler K, Rickert R, Steinhart H: Omega-3 fatty acids and conjugated linoleic acids of longissimus muscle in beef cattle. European Journal of Lipid Science Technology 2002, 104:463-71.
viii Ibid iv
ix Yang A, Lanari MC, Brewster MJ, Tume RK: Lipid stability and meat colour of beef from pasture and grain-fed cattle with or without vitamin E supplement. Meat Science 2002, 60:41-50.
x Ibid ii.