Grain-fed beef healthier than grass-fed?

So says the headline at AgriLife News, a service of Texas A&M University.   A team of researchers led by Dr. Stephen Smith, an AgriLife Research meat scientist, claims to have found that ground beef  has beneficial effects on plasma lipids if made from meat of corn-fed cattle but not if made from meat of pasture-finished cattle.

According to this article, Smith claims:

"We looked at the scientific literature and could not find any justifications for the statement that pasture-fed beef is better for you. All we found were rat studies in which they were fed omega-3 fatty acids, so we wanted to know if this applied to beef from grass-fed cattle."

The team produced ground beef from three types of cattle, one finished on pasture until 20 months of age, one fed a corn-based feedlot diet until 16 months of age, which produced meat graded USDA Choice, and one fed a corn-based feedlot diet until the meat reached USDA Prime grade.  

They took the meat and fat from each set of cattle and created ground beef having 24% fat.  "Next, a group of 27 men completed a three-way crossover study. Each group rotated, consuming five 114-gram ground beef patties per week for six weeks from each of the three sets of cattle used in the study."

According to Smith, "There really were no negative effects of feeding ground beef from the pasture-fed cattle" but

"We did see many positive effects in men that consumed ground beef from corn-fed cattle. The ground beef from the USDA Prime cattle increased HDL cholesterol and LDL particle diameter. Both effects are protective against cardiovascular disease. The Prime ground beef also decreased insulin, so it may have some protective effect against type II diabetes."

So according to this guy, grass-fed beef won't hurt you, but if you want to get healthier, you should eat corn-fed beef. 

Perhaps no surprise, this research was paid for by and presented to the National Cattlemen’s Beef Association, which defends Confined Animal Feeding Operations (CAFOs) and would rather irradiate E. coli laden beef  than employ forage feeding which can reduce E. coli populations in cattle by 1000-fold.  Might this perspective influence the outcome of this "study" which so far as I can tell has not received peer-review?

I am not surprised that the corn-fed beef-rich diet had blood-lipid and insulin-lowering benefits, particularly if the increased dietary beef replaced some carbohydrate-rich foods in the experiment.  I certainly recommend eating corn-fed beef instead of modern carbohydrates.  However, I suspect a conflict of interest underlies this report of no benefits from eating grass-fed beef.