Something Amazing Happens When You Turn 30, Says Science

Our relationships get better — because we get better.

Thirty is an age that causes consternation for many a 20-something. Life gets super serious at age 30, the narrative goes, with career changes, 401(k)s and the inability to party past midnight, not to mention the burning matter of "settling down."

But in reality, your 30s aren't something to fear. They're when things start to get really good, especially when comes to relationships. 

The reason is rooted in science. The cerebellum, directly connected to how we think, "has not finished growing well into the early 20s," says neuroscientist Jay Giedd. Even into our 30s our brains are changing, "pruning away unused connections and strengthening those that remain."

As our brains sharpen, our personalities settle. Research has shown that between the ages of 18 and 30, people become more neurotic, introverted and possibly less open to new experiences (but also more agreeable and conscientious). Those shifts, combined with the life-changing experiences the 20s bring — college, first love, first jobs, traveling — shape our identities, making us much more comfortable with who we are. 

"Around age 30, a sense of acceptance begins to settle in," Ann Friedman wrote. And that acceptance of self makes us much better partners. 

Below, six young adults (single, married and everything in between) discuss how their relationships changed for the better as they turned the corner on 30. There's more to look forward to than we thought.

You don't feel the need to be with someone because society says you should.

Fiona, a single 30-something, was in one serious relationships from ages 18 to 21, then another one from 21 through 28. Now a self-proclaimed "casual dater," she has been able to let go of what others think.

"In my 20s, I was more keen to settle down and move things to the next stages, as society tells us to.  I would say I depended more on the other person than I would now, probably due to immaturity and lack of confidence. I would dedicate more time to the other person, and not enough time to myself or with friends. For a long time my relationship was the most important thing to me, making me a bit blindsided and, in turn, making the breakup significantly harder to deal with.

"These days, I have just become a little more selfish and less willing to compromise. I would now never jeopardize my friendships for the sake of spending more time with a guy. My priorities are different now, and I would be far less likely to rush something, spend every waking hour with a man or choose him over other plans."

You're less insecure, which means you can be more generous with others.

Alastair, single and in his 30s, felt a turning point after his first love in his mid-20s.

"My early 20s I don't think I was as respectful to women as I am now. This was due to a lack of understanding and quite simply I was still growing as an individual. I was too busy with my own insecurities to really be able to comprehend the thoughts and feelings of others at times.  

"Starting in my mid-20s, however, I tried to be myself a lot more. I wasn't so tied up with what people thought, which I think everyone goes through, and I was more respectful. Now I like a partner to have opinions, be passionate, know what they want but to be understanding. I think I have these qualities, so knowing when to give and take is immensely important."

You no longer feel the need to rebel for the hell of it.

Babs, who's in her 30s, has been with one boyfriend since age 22 but had various affairs along the way. Now, still with her boyfriend, she's matured into her long-term relationship.

"Back in my 20s, I'd describe myself as a polygamist who felt the need to appear to be a monogamist. I was experimenting to see what was out there. [My relationship] now is a lot more grown-up. At the start, we were very much in love but incredibly immature. We've both changed a lot, but the relationship has grown with us. At times we do get a bit fed up of each other, but this is always short-lived.

"In some ways, I'm still a free spirit. I'm not a fan of marriage or kids, but I'm very happy at the thought of spending my life with someone. I'm a much better girlfriend now [that] I'm 'behaving.' But that's not just because my boyfriend is awesome, it's because I don't need to."

You stress less about the little things, including relationship drama.

Kaite, in her 30s and married, went through a rocky decade with her now-wife, managing to grow together despite life challenges and a brief split at age 26.

"[My current wife and I] actually met when we were 20 and had a tempestuous but wonderful four-month relationship.

"Our 20s [held] a lot of boundary-setting and trying to work out who we were and what we wanted. It was probably a bit of fighting for dominance, we're both very type A. It's definitely changed. I'm a lot less stressed about things now. [Our relationship now is] calm, steady, supportive and an awful lot of fun!"

You finally feel free to be yourself and accept others for who they are.

Dean, in his 30s and in a long-term relationship since his 20s, was happiest once he let go of what he thought a partner was supposed to be.

"I always imagined meeting someone with the same interests as me, but in fact my girlfriend and I have very different interests. However, as we are both so passionate about the things we love, we are respectful of each other's interests and know how important they are to each of us.

"I feel in my relationship now, there is just more honesty. It's not all about being polite and keeping up appearances, trying to seem cooler than you really are. I think you can just be yourself more. I think that is something that just generally happens as you get older. Things that used to seem important, having the best clothes or being the most popular, just don't matter that much any more. You are with someone who obviously cares about you enough to put up with your bad dress sense or lame jokes, so what does it matter?"

You're more confident in who you are, which makes you more confident about the person you're with.

Ali, in her 30s, first married at 21 then divorced at 27, describing the relationship as "a pretty controlling one." She's now remarried, having shifted her view on what she wants and needs out of a relationship.

"I wasn't settled in myself in any way when I was younger, and I took that out on others. I also kicked against the expectations of the constraint I found myself in — I didn't want to just be a wife, or even really to be a wife. The more it was used to define me, the more I rallied against that.

"I married again this summer, and it's a meeting of equals. It feels completely liberating too, which I hadn't thought marriage could. I think a lot of that is to do with the person I've become in my 30s. I don't care the same about what people think, don't have this idea of who I should be versus who I am, and I think that has a positive effect on relationships. I know it's not limited only to me; my husband feels the same. 

"There's a nice sense at this age of knowing yourself better, and where you fit in the world you've begun to create."