We often think about relationships on a scale from positive to negative. We are drawn to loving family members, caring classmates and supportive mentors. We do our best to avoid the cruel uncle, the playground bully and the jerk boss.
But the most toxic relationships aren't the purely negative ones. They're the ones that are a mix of positive and negative. We often call them frenemies, supposed friends who sometimes help you and sometimes hurt you. But ifs not just friends. It's the in-laws who volunteer to watch your kids but belittle your parenting. The manager who praises your work but denies you a promotion.
Everyone knows how relationships like that can tie your stomach into a knot. But groundbreaking research led by the psychologists Bert Uchino and Julianne Holt-Lunstad shows that ambivalent (矛盾情绪的) relationships can be damaging to your health — even more than purely negative relationships.
I had assumed that with a neighbor or a colleague, having some positive interactions was better than all negative interactions. But being cheered on by the same person who cuts you down doesn't reduce the bad feelings; it increases them. And it's not just in your head: It leaves a trace in your heart and your blood.
Even a single ambivalent interaction can cause harm. In one experiment, people gave impromptu speeches on controversial topics in front of a friend who offered feedback. The researchers had randomly assigned the friend to give ambivalent or negative comments. Receiving mixed feedback caused higher blood pressure than pure criticism. "I would have gone about the topic differently, but you're doing fine" proved to be more distressing than "I totally disagree with everything you've said."
The evidence that ambivalent relationships can be bad for us is strong, but the reasons can be harder to read — just like the relationships themselves.
The most intuitive reason is that ambivalent relationships are unpredictable. With a clear enemy, you put up a shield when you cross paths. With a frenemy, you never know whether Dr. Jekyll or Mr. Hyde is going to show up. Feeling unsure can disrupt the body's calming system and activate a fight-or-flight response. It's unsettling to hope for a hug while also preparing for a likely quarrel.
Another factor is that unpleasant interactions are more painful in an ambivalent relationship. It's more upsetting to be let down by people you like sometimes than by people you dislike all the time. When someone stabs you in the back, it stings more if he's been friendly to your face.