According to the University of Michigan, you start to become more and more like your partner – physically. They studied over 15-hundred married couples. And they found that as couples grew old together, they became more physically similar. There were similarities in things like kidney function, cholesterol levels, and grip strength.
So why would this happen? Well, they theorize that not only do we tend to choose partners who are similar to us – as far as age, background, and looks. We also spend our lives together – eating the same foods, living in the same place, and sharing activities. So it makes sense that the more similarly we live – the more alike we become.