Grass-fed beef has been marketed hard lately and most consider it to be vastly superior to grain-fed beef. Among the most common stated reasons are because grass-fed beef has a better nutritional profile and the cows aren’t given hormones making them more natural and thus better for you. Using logic it would make sense, it’s just common sense right? Well if you’ve been reading my material for any decent amount of time you know by now I don’t believe in common sense. So let’s take a closer look.
The first thing I’d like to take a look at is lipid profiles shown in research by Leheska et al. (2008.) When breaking down the lipid profiles of grain-fed vs. grass-fed beef they following difference were discovered:
Saturated fatty acids – Grass-fed 50.9 grams, Grain-fed 44.5 grams.
Monounsaturated Fat – Grass-fed 39.2 grams, Grain-fed 47 grams.
Omega 3’s – Grass-fed .88 grams, Grain-fed .24 grams.
Omega 6’s – Grass-fed 1.85 grams, Grain-fed 2.20 grams.
Taking a look at those numbers it would appear grain-fed actually has more of the “good” fats and less of the “bad” fats although grass-fed has slightly less total fat. Where grass-fed had the big advantage was in omega-3’s which are absolutely a good thing. However when you look at the overall picture the difference between the two is not that great. I’d give a slight advantage to grass-fed because of the omega-3’s. (1)
In a review of several studies looking at the fatty acid profiles and antioxidant content in grass-fed and grain-fed beef the results are clear. Grass-fed is higher in CLA, antioxidants, vitamins and minerals as well as omega-3’s. Of course there is a wide variation in the studies especially depending on what kind of breed was used. For instance when crossbred steers were used in 2009 by Alfaia et al. grass-fed had about double the CLA as grain-fed. When using Angus steers in 2006 Ponnampalam et al. showed grain-fed actually had slightly higher CLA. However for the most part CLA and omega-3 was higher in grain-fed in the majority of studies. (2)
Besides the nutritional profile the other thing that comes into play, and it seems to be a big one for many, is the hormones used in grain-fed cows. Grain-fed beef is often implanted with growth-promoting hormones to help increase the efficiency of the feed being converted to muscle. These hormones are tested and approved by the FDA before they are available to producers.
Let’s talk about one of the most common hormones implanted, estrogen. A serving of beef contains .3 billionths of a gram of estrogen which is over 50,000 times lower than the FDA allows. When comparing estrogen in grass-fed and grain-fed beef the difference is minimal to say the least. A 3 ounce serving of grass-fed beef has 1.3 nanograms of estrogen in comparison to 1.9 nanograms in grain-fed. To put into perspective just how insignificant that is 4 ounces of raw peas has 454 nanograms of estrogen, 4 ounces of raw cabbage has 2,700 nanograms of estrogen, and if you are really worried about those hormones make sure you never use soybean oil as a 3 ounce serving of that contains 168,000,000 nanograms of estrogen. Surely that would kill you instantly.
Obviously I’m not buying the hormone argument but I won’t judge anyone who wants to stay away from anything because it was given hormones. I do, however, fully support that the nutritional profile of grass-fed beef is greater than grain-fed, but I think the difference is minimal and for there to be a significant difference the amount you would need to eat would make the omega-3 content the last thing you need to worry about.
Now the real question becomes because you are getting higher levels of some nutrients in grass-fed does it make it worth the extra money? After all if you haven’t noticed grass-fed beef comes at a pretty hefty price. The answer really comes down to what’s important to you and how much you are willing to spend. In my opinion I don’t think spending that much extra money for an extra .6 grams of omega-3’s and a couple more grams of CLA is worth it. If you don’t have the extra money I don’t see any reason to believe you are negatively impacting your health by choosing grain-fed beef. If you don’t mind spending the extra money grass-fed beef will give you a slightly better product.