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March 14, 2008 -- Yak cheese may have certain nutritional advantages over conventional cheddar cheese, a new study shows.
Researchers in Canada and Nepal compared the fatty acid profiles of two types of cheese:
The yak cheese was three times higher in omega-3 fatty acids than the cheddar cheese. Omega-3 fatty acids have been studied for various health benefits, including heart health. In particular, yak cheese was rich in alpha-linolenic acid (ALA), a type of omega-3 fatty acid also found in flaxseeds and other plants.
The yak cheese was also richer in conjugated linoleic acid (CLA), which has been shown to have "a range of positive health benefits" against cancer, body fat gain, type 2 diabetes, and other conditions, according to the researchers, who included Professor Brian McBride, PhD, MSc, BSc, of Canada's University of Guelph.
"The results suggest that cheese from yak, grazed on Himalayan alpine pastures, may have a more healthful fatty acid composition compared to cheese manufactured from dairy cattle fed grain-based diets," the study states.
McBride's team didn't compare cheese from grass-fed cows to yak cheese. But the findings aren't just about what the yaks and cows ate, according to McBride.
"The yak cheese profile reflects a combination of the effect of their unique diet and their endogenous microflora [natural bacteria] within their rumen," McBride tells WebMD via email. The yak's rumen is the "fermentative component of their stomach," McBride explains.
The study wasn't an exhaustive comparison of all the nutrients in yak cheese and cheddar cheese -- just fatty acids. The researchers aren't promising health benefits from yak cheese, and they're not calling cheddar cheese unhealthy.
How did the yak cheese taste and smell?
"The cheese flavor and smell was similar to a medium cheddar cheese," McBride says.
Cheddar cheese is widely available. Yak cheese is sold in some gourmet food stores, according to the American Chemical Society, which published McBride's study in its Journal of Agricultural and Food Chemistry.
One of McBride's colleagues works in Katmandu, Nepal, for the nonprofit Asia Network for Sustainable Agriculture and Bioresources.