Non-cat owners appear to have a 40 percent higher risk of dying from myocardial infarction than those who do have a cat, according to a study presented at the American Stroke Association's International Stroke Conference last month in New Orleans. Researchers examined the data of 4,435 people from the second National Health and Nutrition Examination Survey. (Dogs didn't factor into the findings because fewer participants owned them.)
Picture via Flickr user avidpets
http://www.chron.com/disp/story.mpl/pets/5599262.html via Evangelical Outpost
And in response to MoonCake's comment, I don't think it quite works that way. I grew up with cats and it hasn't made me any less allergic.
People with dustmite allergies live in the constant presence of dustmites (there is no escaping them, they're EVERYWHERE), and as far as we know, this doesn't reduce their allergic reactions.
I suppose we could do an experiment, but there would be no way of having a control no-dustmite group unless we locked those subjects naked in a plastic bubble with no fabric.
And is it really healthier to give love to something that couldn't care less if you didn't come home one night? Dogs are always glad to see you. Cats? Not so much.