Why you should tell a friend about that embarrassing thing that happened

By Kara Alaimo, CNN

(CNN) — Telling your boss or date that thing you weren’t sure you should reveal could be good for you.

People often hold back too much, according to behavioral scientist Leslie John, a professor at Harvard Business School.

Instead, you should share personal things with others, John argues in her new book, “Revealing: The Underrated Power of Oversharing.” Hopefully they will reciprocate, and you can keep going back and forth by sharing. That’s how you can deepen relationships that are vital to your life, according to the book.

I spoke to John about why sharing more can make people healthier and happier, how to decide whether to do it, and why she carries light bulbs with her when she travels.

This conversation has been lightly edited and condensed for clarity.

CNN: You say if we share more about ourselves with other people, we’ll get more of what we want in life. How?

Leslie John: We need people to trust us in order to get things like love, friendship and career success. When you make yourself vulnerable by revealing something sensitive, it makes other people trust you.

We’ve done studies that show that if someone says, “You can trust me, you can tell me anything,” people become less comfortable than if you say nothing at all.

We want to be shown people can be trusted. One really powerful way you show it is by being vulnerable and putting yourself at risk.

CNN: You warn we shouldn’t share everything, so how do you decide what to reveal?

John: First, you want to think about your goal. What’s your purpose? What are you seeking? Maybe this person is an acquaintance, but I’d like to spark a friendship with them.

We naturally think through the risks of sharing. We think, “Oh my god, if I tell my boss this, they’re going to fire me, they’re going to think I’m incompetent.” That’s great, that’s an important consideration, and it comes naturally. But we need to make sure to think about the downsides of concealing and the benefits of opening up.

The No. 1 thing we underlook in these decisions are the downsides of concealing. For example, “If I don’t tell my boss this, I’m going to ruminate, it’s going be on my mind forever.” We underestimate the psychic cost of keeping a secret. Keeping secrets is linked with negative physical and mental health.

You can make boxes and fill in the pros of revealing, pros of disclosing, cons of revealing and cons of disclosing.

You’re not going to have a full four-quadrant reckoning for every decision, but if you start doing this with some of your big ones, it comes more naturally to you. And you’ll make these decisions in a more enlightened way.

CNN: Why is lighting so important?

John: When experimenters put people in a cozy room and ask them sensitive questions or engage in a therapy session, people are much more revelatory. A soft room would be a room with sub-3000K lighting, cushy things in it, cozy blankets and carpets instead of hardwood floors.

My thesis is that when you open up and do it right, you get many benefits. So, if I’m having a hard conversation with my husband, I want to be in our cozy room. I don’t want to be in our kitchen with superbright lights.

I pack them for when I’m not home because the world and hotels are full of terrible, non-cozy, over 3000 Kelvin light bulbs and I can’t stand it! Lighting is one of the easiest ways to make things cozy.

CNN: Dating profiles are an exception to your advice to reveal more. Why?

John: When you put a lot of stuff up there, prospective dates will find things they really love and relate to, but the more you have, the more chances they’ll find stuff that makes them think, “That person’s not for me.” And it turns out that seeing something that you can’t relate to or is dissimilar to you in those early stages is more of a turnoff than finding points of similarity is a turn-on.

So, it’s much better if you put just a few details that describe you but are also likely to be fairly resonant. It’s even better if you induce curiosity. You can write, “Ask me about the time when,” and say something enticing.

Another thing that distinguishes profiles that get more hits but is really uncommon is expressing interest in getting to know the other person — something like, “I love hedgehogs, and I’d love to know what your favorite animal is.”

When you show you’re interested in someone it makes them like you more, because people like to be asked about themselves. It also signals something deeper, that you’re discriminating. You’re choosy. And that’s a nice turn-on.

Then, as things progress, you want to get deeper, and you don’t want to be holding back.

CNN: You say “mind-reading expectations” cause people in long-term relationships to grow apart. How so?

John: Long-term relationships break down for a lot of reasons, but surprisingly they are more likely to break down from growing apart than from something dramatic, like someone having a sordid affair.

People end up lonely in marriages. A reason for that is because when we are with someone for a long time, we know them better over time, but our confidence that we know them outpaces our actual knowledge of them.

That’s where the problem begins. If you’re overconfident you know what your spouse is thinking and feeling and their momentary worries, you stop asking. If you don’t ask, the other person doesn’t share and so you stop sharing. That’s the mechanic of what happens. And then you wake up one day, and you feel like you don’t know each other.

This is compounded by something called mind-reading expectations — the belief that your partner should just know what you think and feel. They should be able to read your mind. When you say it like that you realize how absurd it is, but these beliefs are really insidious and deep.

I realized as I was writing this book that I had them. I realized I need to not assume. I need to keep asking and sharing and telling my partner how I feel, because he can’t guess my mind.

CNN: You say talking about painful experiences with a friend or therapist can really help our health and well-being. Why?

John: Many, many studies have shown that when you reveal sensitive thoughts and feelings it causes you to be better physically and mentally – and as a scientist, I don’t use the word “cause” lightly.

If you don’t have money for a therapist and you just write down the things that are bothering you in a diary, over time you will feel better about those things. You’ll be happier, and you’ll have greater well-being.

The psychological reason why it’s so helpful is that you make sense of these events. When we write things down, or when we say them out loud, it naturally forces a story structure. And that story structure is what helps us cope and find meaning or grow.

On top of that, if you’re talking to a person who cares about you, you will do better processing just knowing you have an audience because you need to make more sense of it for them. Having an active listener is also more potent to help you feel supported and get through these things.

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