Is grass fed beef leaner than regular beef?

I was having a debate the other day with a friend and he was saying that beef from a cow that has been all natural grass fed on the free range is leaner than regular beef.

Any truth to this?

NM, answered my own question via Wiki.

Fats

While grass-fed beef contains less total fat compared to grain-fed beef, grass-fed beef and dairy contain higher levels of Conjugated Linoleic Acid (CLA) and the Omega-3 fatty acids ALA, EPA, and DHA. [1]. While the research on CLA is unclear with regard to humans, it has shown many positive effects in animals in the areas of heart disease, cancer, and the immune system.

jpeac2 wrote:I was having a debate the other day with a friend and he was saying that beef from a cow that has been all natural grass fed on the free range is leaner than regular beef.

Any truth to this?

Not to split hairs too finely, but I believe most beef that is advertised as "grass fed" has been finished on corn during the final months of its short life.

theres really very little difference in total fat between the two.
(as long as the feed lot cattle weren't overfed, as this causes high fat, the difference is its not intra muscular fat)
the biggest difference is breed of cattle.
for example the dairy breed Jersey which is prized for its high milk fat, has very fat beef also.
whereas the dairy breed Holstein which has been raised for high volume milk production has very little fat, as animals that are storing fat are not using all available energy for milk production.

the same is true for beef breeds, angus are raised to create good marbling and are fairly fatty. becuase they are storing energy as fat they don't gain much weight on a all grass diet.
you are more likely to see an old world breed such as hereford raised on grass, as they don't waste as much energy on fat, they perform better grazing.