Like most things, the matter of the cellulose in parmesan cheese is actually a little more complicated. On my last post, a friend commented and explained that wood pulp is cellulose. (Thanks my friend!) I looked it up and it is! It acts as fiber in our digestive system that moves things a lot because it isn't digestible by human bodies. Hmm... I gathered from what I read online that it hasn't been determined whether it is dangerous for human consumption. The FDA has approved it as a food additive. That's why the article is funny to me. I suspect there are probably limits of how much cellulose is added (though I'm not sure) and it is very important that food is correctly labeled. I suspect that is one of the larger issues. The article makes it seem like the wood pulp is dangerous.
Sifting through what I read a little more from the article I linked to and other sources I found online, I believe the issue is more with false labeling. A cheese seems like it couldn't be 100% Parmesan Cheese if 3-4% of it is cellulose, aka wood pulp. It is also disconcerting that Target's store brand grated Parmesan isn't at all parmesan. The cellulose does keep it from clumping and sticking together.
Here's a link to a second article: http://www.huffingtonpost.com/entry/cheese-wood-pulp-cellulose-parmesan_us_56c491c2e4b08ffac1271f1e
This article explains that 2-4% is allowed. The cheese in question was tested at 7.8%, far higher than the allowable limit. Kraft's cheese is within that limit.
Here's the FDA's statement about cellulose on their website: http://www.fda.gov/Food/IngredientsPackagingLabeling/GRAS/SCOGS/ucm261248.htm
I still think it's funny. "Wood Pulp" is used to alarm us. "Cellulose" is used to make us think it's just something else added to food. It's all about the spin!