Bernard O'Shea: Five things I wish I’d known in my 30s (but only learned in my 40s)
Bernard O'Shea: "Scientifically, it turns out your 40s genuinely are a turning point. Your muscle mass naturally starts dipping every year after 30 unless you 'maintain a strength-training routine'. A routine! I’m lucky if I manage to bring the bins out without needing a three-minute bsit-down on the wall."
In my 30s, I thought I was invincible. I’d play five-a-side twice a week, then go home, eat a pizza at 10pm, and my body would just… process it. No complaint, no invoice, no follow-on meeting.
But in my 40s? I actually think some mornings someone snuck into the room that night and beat the living shit out of me.
Scientifically, it turns out your 40s genuinely are a turning point. Your muscle mass naturally starts dipping every year after 30 unless you “maintain a strength-training routine”.
A routine! I’m lucky if I manage to bring the bins out without needing a three-minute sit-down on the wall.
You don’t fully appreciate your body in your 30s because it’s like a rental car: you assume someone else is responsible for the long-term maintenance.
But your 40s are the moment that the rental company shows up with a clipboard and says “What happened here?”
In my 30s, I’d nip into town at 1:40am, have a few late-night pints like you were cementing a lifelong pact, and boom — best friends forever.
I assumed those relationships would stay magically alive because they were strong once.
In my 40s, I realised friendships don’t disappear — they just slowly drift. No rows. No fallouts. Just… entropy.
Life gets busy. Kids start doing 400 activities. Someone moves to Australia.
Before you know it, you’re saying things like “We must meet up”... even though the next available date is 2031.
Psychologists now say that social connection is as important to your health as diet and exercise.
There’s an actual Harvard study — 75 years long — that found the biggest predictor of happiness was stable friendships.
Seventy-five years! Not one mention of step counts or oat-milk lattes. Just have a few good friends.
In my 30s, I was terrified of disappointing people.
Someone would ask me to do something mildly inconvenient, and I’d agree so quickly you’d think they offered me a kidney.
Culturally, Irish people struggle with boundaries. We treat ‘no’ like it’s a personal attack.
If you say no to someone in Ireland, you immediately have to provide a detailed medical explanation, a note from your GP, and a photograph of the affected limb.
Meanwhile, other cultures say no all the time. French people say no before you’ve finished asking the question. Americans say no enthusiastically — like it’s self-care. We say no only if we are physically unable to speak because someone has stolen our lungs.
A 2021 study in the Journal of Social Psychology found that people who set boundaries are happier, less stressed, and less resentful. The researchers said it leads to “greater emotional well-being”.
Saying no doesn’t make you selfish. It makes you sustainable. In your 30s, you think you’re a power bank with infinite charge.
In your 40s, you realise you’re more like the batteries that have been in the telly remote control forever — reliable, but you have to give them a good rub every now and again.
There is a moment in your 40s when time shifts.
It happened for me standing in the middle of the kitchen on a Tuesday, holding school shoes, three lunchboxes, and a half-eaten Supermac’s chip, handed to me by a child who vanished again immediately.
I looked around and suddenly realised: This is life. Not the stuff you plan. Not the big events. This chaos.
In my 30s, time felt infinite. I’d waste whole evenings scrolling, whole weekends doing nothing, whole mornings trying to fix a hangover using hydration strategies that were questionable at best.
I thought I’d “get to it eventually”.
‘Eventually’ was this magical place where future-me lived — a man who was well-rested, productive, and knew where his passport was.
But the 40s hit differently. Time tightens. Weeks vanish. Your kids grow overnight.
Someone says “Sure, it’s nearly Easter” and your soul leaves your body because how? You were only putting the tree away yesterday. You can’t slow time, but you can notice it.
Here’s the thing nobody told me in my 30s: happiness is not a grand event.
It’s not a promotion. It’s not buying a house. It’s not even finishing the kitchen renovation without crying in a tile shop.
Happiness, when you get to your 40s, is almost embarrassingly small.
For me, it was the moment all three kids were strapped into the car and silent. Not asleep. Just… not shouting.
I stared out the windscreen and felt something warm bloom inside me. Peace? Joy? Or maybe the early signs of another mini-breakdown — you never know at this age.
We are obsessed with big milestones. Leaving Cert. 21st. Wedding. Mortgage. Kids. Pension. Retirement.
Each one was treated like a boss level you had to pass. Growing up, happiness was always pitched as a destination.
“When you get X, you’ll be sorted.” But X keeps moving.
My 30s were spent chasing happiness like it was some mythical creature hiding in Ikea.
My 40s taught me it was in front of me the whole time — in the quiet car, in the decent cup of tea, in the chat with a friend you finally texted, in the moment the dishwasher actually seals.
Happiness is small. But if you add up all the small things, you get something big enough in the end.
