Consumers choose USDA grass-fed beef for the following four main reasons: taste, health concerns, ecological awareness and local fare. Producers of grass-finished beef have heavily targeted a health-conscious customer base.A grounding look at the product’s nutritive contents may support alterations to grass-finished beef’s marketing strategies.

As a ruminant nutritionist, I understand that “you are what you eat” somewhat applies to humans and other monogastrics (pigs, horses, etc.), but not quite as much to ruminants like cattle.

Because of the fermentative action of rumen microbes, what a cow actually digests is much different than what she originally ingests. The dogma “you are what you eat eats” misrepresents the conversion of a pure forage diet into beef and its nutrients. Anyone surprised by the actual nutrition facts can blame it on the rumen.

Rumen microbes interfere with the diet’s fatty acid profile. Plant-based oils like Omega-3s are toxic to rumen biota because they disrupt microbial membranes. In defense, microbes hydrogenate these unsaturated fatty acids and create saturated fatty acids (SFA). This process of ruminal hydrogenation creates two fatty acid intermediates: conjugated linoleic acid (CLA) and trans-vaccenic acid (TVA).

Forage-based diets pass more slowly from the rumen to the true stomach than do grain-based diets, which extends the time for microbial alteration. As animals spend more time growing on grass rather than on grain-based diets, SFA, CLA, TVA and Omega-3s accumulate in animal tissues. Conjugated linoleic acid has received positive attention for some laboratory animal studies showing reductions in arterial blockage, malignant tumor size and total body fat.

While its benefits are still unconfirmed by human studies, grass-finished beef can offer up to two or three times as much CLA as conventional beef. However, either conventional or grass-finished beef can still be a good source at ranges of 0.1 to 0.15 g per serving.

Unfortunately, trans-fats such as TVA can increase arterial blockage by increasing LDL cholesterol, lowering HDL cholesterol and increasing triglycerides. Cholesterols LDL and HDL have opposite roles in the bloodstream: LDL deposits lipids that can create arterial blockages, while HDL removes lipids to keep arteries clear.  That is why LDL is considered “bad,” while HDL is considered “good” cholesterol.

Some health experts have praised grass-finished beef for its increased Omega-3 content. Omega-3 fatty acids may improve human health by improving circulation, lowering triglycerides and blood pressure, as well as showing anti-depressant and anti-arthritic effects.

Although grass-finished beef has statistically significantly higher amounts of Omega-3s than grain-finished beef (0.052 vs. 0.039 grams per three-ounce serving, respectively), the difference is quite minor compared to sources such as wild salmon (1.83 grams per three-ounce serving).

Because the daily recommended intake of Omega-3s is 1 g, a serving of grass-finished beef would offer less than 10 percent. The accumulation of CLA, TVA and Omega-3s competes against marbling and monounsaturated fatty acid (MUFA) synthesis. Intramuscular fats and MUFAs become reduced as cattle subsist on an all-forage diet. Olive oil won its heart-health fame from MUFAs because they increase HDL cholesterol.

Grain-finishing cues the activity of a desaturase enzyme that converts SFA in a steer’s tissues to MUFA. Grain-finishing increases marbling, Omega-6 and MUFA content. The ratio of Omega 3 to 6 in grass-finished beef, being lower than conventional beef, is more optimal (about 1:4 vs. 1:10).

Another noteworthy ratio in beef is MUFA:SFA, which directly impacts cholesterol HDL:LDL in human consumers. Grass-finished beef has less MUFA than SFA (ratio of 0.7 – 0.9), while conventional beef has an optimal ratio of 1.1 – 1.3.

Keep in mind that either grass-finished or conventional beef’s positive “ratio” will be canceled out by over-consuming Omega-6 or SFA in other parts of the diet, so that a person’s overall dietary ratios may be far from optimal. People watching for these ratios should stay consistent in all meals, not just those containing beef.

Evidence supporting grass-finished beef’s nutritional and ecological superiority over conventional beef continues to reveal limitations as scientific pursuit continues. Producers of grass-finished beef might redirect marketing away from health claims and toward the unique intricacies of grass-finished taste and artistry. Producers that specifically market grass-finished beef as a health-solutions product give it no competitive edge against imports.

Consumers buying grass-finished beef for wellness issues alone will bypass American grass-finished beef for cheaper South American or Australian beef. An artisanal product like grass-finished beef deserves more celebration of its terroir, a French word that depicts intrinsic flavor nuances based on a food’s area of origin.

The high variability in flavor is a value-added trademark of grass-finishing. The niche product offers highly desirable traits as a localized product with a taste that is not replicable. However, nutritional superiority over conventional beef should not be counted among the selling points that will sustain consumer demand for grass-finished beef.  

References omitted due to space but are available upon request.

Cassie Payne, M.S., is a frequent speaker for the Texas Beef Council. This article came from a presentation at the Texas A&M Grass-fed Beef Conference. Contact her at catherine.p.payne@gmail.com

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Producers and consumers should study the claims on health benefits to grass-fed beef and determine what is sound nutrition science. Photo by Philip Warren.