I'm not sure why there's seldom heard a discouraging word when you're home, home on the range. But this might be one of the reasons: superior nutrition from the meat of free-range animals.

If you only needed one reason to eat beef from free-range livestock, omega-3 content would be an excellent reason.

Grass-fed animals produce meat that's very high in omega-3 fatty acids compared to factory-farmed animals that are fattened with grain feed. This is one reason why meat-eaters of a century ago were generally in better health than meat-eaters of today.

But omega-3 is just one of the healthy benefits. Here are five more reasons to choose grass-fed beef over factory-farmed beef:

In addition, when animals are free to move about in large pastures, disease risk is much lower, so the need for antibiotics is dramatically reduced. But in factory farming, disease is so common that virtually all animals are given antibiotics. Then antibiotics end up in the meat, consumers eat the meat, and this contributes to our society-wide resistance to antibiotics.

That alone is disturbing enough. But there's more: E. coli – the bacteria with certain strains that prompt severe illness. A Cornell University study found that grain-fed animals contain about 300 times more E. coli than grass-fed animals.

Also, something about the grain feed makes E. coli more acid resistant, so the bacteria are more likely to survive the trip through our stomach acids. Harmful E. coli in grass-fed beef is neutralized more efficiently in the stomach.