Let’s start with a fascinating piece of research. Earlier this year, a scholar at NYU named Bingkuan Li published a study in the Proceedings of the National Academy of Sciences. He tracked 2,345 American adults, using DNA methylation to measure their real biological age—not the number on their ID, but the aging at the cellular level. At the same time, he asked each person to describe their social circle: do you have anyone around you who consistently causes you distress, drains you, someone you find hard to deal with?
The result: for every "difficult person" in your life, your biological aging speed accelerates by 1.5%. The more such people you have, the faster you age.
Now, a "difficult person" here has a certain threshold. First, they are remarkably consistent in being difficult—they never disappoint in that regard. Second, they are "long-term" and you have to interact with them regularly.
Most people’s first reaction is: I need to identify these people and stay away from them. That’s a perfectly normal response. But today, let’s explore a different perspective—one that doesn’t just label people as "toxic" and cut them off.
That perspective comes from a scholar named Leanne ten Brinke, who just published a book called Toxic People. She defines "toxic people" as those who tend to cause discomfort, pain, and emotional drain in those around them. She’s studied this topic for over 20 years, making her one of the most credible voices in this field.
Brinke’s first key insight: the world is complex, and so are humans. Apart from a very small number of people who are "exceptionally good" or "exceptionally bad," most of the time you can’t simply define someone as good or bad.
Consider the example of William O. Douglas, a former U.S. Supreme Court Justice who served for 36 years—the longest in history. In public, he championed free speech, opposed government surveillance, and stood with marginalized groups in key rulings. After his death, many law schools and lectures were named after him. By all accounts, a great man.
But Brinke argues that by modern diagnostic criteria, Douglas likely fits the definition of a psychopath. Why? Because while his public achievements are real, in every private relationship—wives, children, colleagues, assistants—he left behind a trail of ruin. He was married four times, each ending in infidelity. His children cut ties with him. His assistants were treated as tools, used and discarded without regard for their well-being.
The point is not to cancel Douglas. The point is that the same person can be both "toxic" in personal relationships and "admirable" in public life. This complexity forces us to move beyond the simple "identify and avoid" framework.
So how do we really deal with difficult people? Brinke suggests we stop asking "Who is toxic?" and start asking "What situations make a normally decent person behave in a toxic way?" Many so-called toxic behaviors are actually situational—people under extreme stress, power imbalance, or unresolved trauma can become temporarily unbearable. That doesn’t excuse the behavior, but it gives us a more useful lens: we can either change the situation, change our distance, or change our reaction.
The next time you encounter someone "hard to deal with," don’t rush to label them. Pause. Consider the context. And remember: the person who annoys you the most might be the one teaching you the most about your own boundaries.