Chances are, everything feels a little different when you've been in the same relationship for a long time. And it turns out scientists have some evidence to back that up.
The research is a little difficult to pin down. Like Tolstoy, scientists have spent more time studying unhappy relationships than happy ones, which means there's less out there than you might expect.
Plus, everyone — including scientists — defines a long-term relationship differently. Researchers think about couples in many ways: married, cohabiting, together 20 years, together 50 years, madly in love. That means some of the findings included here may apply to only one particular subset of people in "long-term" relationships.
But here are a few of the most intriguing observations scientists have made.
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1. You begin to think other romantic prospects are less attractive.
Don't remember meeting any attractive singles lately? It turns out a quirk of your brain may be making you less likely to cheat by toning down the looks of other possible partners.
That's the conclusion of collection of studies looking at how people in relationships — and particularly in happy relationships — see other people.
2. Your struggles become your partner's struggles.
That's not just because they have to listen to all your complaints about your terrible boss.
It turns out that if one partner becomes more depressed over the course of a relationship, the other is likely to follow, according to one study that tracked marriages for almost 15 years. The researchers found a similar connection when one partner had trouble completing daily tasks.
One possible explanation the researchers have suggested is that when one partner becomes more sedentary and more of a homebody, the other follows.
3. Some weird physical traits may sync up.
It's not just your mind that's affected by a long-term relationship — your body can change too.
One recent unpublished study of people who had been together for a half century found that partners have similar results on three physical fronts: kidney function, cholesterol, and grip strength.
That's an eclectic collection to be sure, and most partnerships won't last 50 years. (We'll also have to wait and see if the preliminary results hold up.) But the findings suggest that for some conditions, if one partner starts to see health problems, the other should be checked as well.
See the rest of the story at Business Insider