Since I'm no sociologist, how do these researchers go about determining whether correlation = causation? I myself would tend to come to the opposite conclusion, that healthy motivated people with good vitals are more likely to put more effort into their marriage, because being healthy just makes you feel better in general. I've been married for 10 years, 2 kids, and I look forward to seeing my sexy wife because she makes an effort to keep herself looking good, and I put in the same effort. I think having the good vitals mentioned in this article improves your outlook on every aspect of life, but of course it's just one factor coming into play with money, time, other relationships, etc.