Being the hopeless romantic, I worked hard last year to come up with just the right thing to say to my wife on Valentine’s Day. I decided to let my lovely bride know that I really liked her signaling traits. Sadly, that didn’t go over so well.

This year, I think I am going to tell my wife that I like the way she smells.

I don’t know how Amy will receive my romantic overture, but I do know that scientific research explains the preference I have for my wife’s odors—it reflects the composition of a key component of her immune system, specifically her major histocompatibility complex. And, my wife’s immune system really turns me on.

Odor Preference and Immune System Composition

Why am I so attracted to my wife’s scents, and hence, the composition of her immune system? Several studies…