I believe grass-fed beef and bison are healthier meat choices than “conventional” grain-finished animals. Yes they may be more expensive because it takes more time and land to finish them, the meat won’t be as tender because fat marbling is reduced or absent, and the meat may have a “grassy” taste. But here are the reasons why I think grass-fed beef is better for both the consumer and the environment:
• Grass (and hay) are the normal diet of ruminants; the heavy corn and grain diet upsets their digestive systems which increases risk of bloating, makes the stomach more acidic, and increases the need for antibiotics (which likely contributes to the development of resistant “superbugs”)
• Grass-fed beef has a lower overall fat content; the fat in grain-fed marbled meat is more difficult to trim off
• Grass-fed beef contains 3 to 5 times more conjugated linoleic acid (CLA), a beneficial fatty acid shown to prevent cancer and reduce abdominal fat while increasing muscle. The natural form of CLA found in meat is more effective and safer than that sold in supplements.
• The Omega 6:Omega 3 ratio is closer to the ideal of 1:1. A study by North Dakota State University found the Omega 6:3 ratio was 4:1 in grass-fed bison and 21:1 in grain-fed bison.
• Grain-fed beef has a higher vitamin E content
• E. coli bacteria thrive in the acidic stomachs of grain-fed ruminants, increasing the risk of meat contamination
• Fossil fuel consumption is higher in the production of grain for feed, and in the distribution of manure from feedlots, thus contributing more to climate change (although grass-fed animals produce more methane)
• Finally, increasing grass-fed beef requires more land in grass which benefits grassland birds [http://trevorherriot.blogspot.com/2009/03/to-make-prairie-part-ii-grass-fed-beef.html]
For more discussion on this topic see www.mercola.com/beef/references.htm or www.johnrobbins.info/blog/grass-fed-beef/. The book “The Omnivore’s Dilemma” by Michael Pollan (2006) looks at this issue within a larger context.