I KNEW IT! Cheese gives me a happy feeling, more than just about any other food. If the casein in cheese does indeed break apart during digestion "to release a whole host of opiates called casomorphins" then I don't know why it isn't even more addictive.

However, I looked for confirmation about cheese releasing opiates, and this is the closest I could find in related research:

"..beta-Casomorphine-7, a naturally occurring product of cow's milk with opiate-like activity, was studied for possible direct histamine liberation activities in humans. It was found to cause concentration-dependent in vitro histamine release from peripheral leukocytes of healthy adult volunteers. Intradermal injection of beta-casomorphine-7 induced a wheal and flare reaction in the skin similar to histamine or codeine." (A naturally occurring opioid peptide from cow's milk, beta-casomorphine-7, is a direct histamine releaser in man. - PubMed - NCBI)

Idk about the moral center of the statement made that it actually releases opiates.. was just looking at the site of the guy who said it (Dr. Barnard's Blog | The Physicians Committee) and it's very marketing-heavy... Plus no one else seems to be saying this, which makes me very suspicious that he's just ensuring he gets quoted/mentioned. ("While it's still debated just how much of an opioid effect casomorphins have, some food scientists go so far as to describe cheese as 'dairy crack,' as Barnard did in the Vegetarian Times." If You're Basically Addicted to Cheese, There Could Be a Good Reason Why - Mic)

Thank goodness, because I would really struggle to have to give up cheese. It's one of very few and very mild pleasurable vices I have left. I'm eating it right now. This news item made me hungry.