As I approached my 40th birthday, I came across a chart that would – without exaggeration – alter my life’s course. Known as the U-shaped ‘happiness curve’, it plots life satisfaction across adulthood. It suggests that people are, on average, happiest in their 20s, and in old age. The bit that bothered me was the middle: according to the chart, my 40s promised to be my glummest decade.

Shortly after I saw this graph, I made some major life changes – determined to buck the averages. I took a career break, lived abroad for a year, refocused my attention on family, and decided to write a book. Generally, I think it worked: I’m about to turn 45, and now feel pretty content.

So imagine my surprise to learn recently that the chart is more debated than I assumed. While the evidence (600+ papers, apparently) supports the U-shape, its applicability to you or me, well… it depends. For example, in some countries, older age doesn’t necessarily bring greater contentment, particularly if welfare support is lacking (and in some societies, midlife is the peak of wellbeing). There may also be gender differences: the mid-40s slump could be skewed by particularly unhappy men.

This year, the entire shape of the curve has been questioned. It seems the young may be unhappier than previous generations, which is flattening out the classic smile-shape into something more like Mr Spock’s arched eyebrow. In sum, it’s more complex once you dig into the data.

However, I have no regrets about making midlife decisions based on a chart. The real power wasn’t in the curve’s accuracy, but in how it gave me permission to make positive changes. And growing older has taught me that, sometimes, life’s big choices must be made with imperfect information.

Just breathe! When you’re gripped by anxiety, hearing this well-intentioned advice can be infuriating. Compared with the power of my body’s fight-or-flight response, the notion that I can find calm by tuning into my breath feels almost fanciful.

But recently I came across a study in Scientific Reports that caught my eye because it showed that slow breathing makes a difference not just to how people feel, but to their brain activity. The results have increased my confidence that breathing can make a meaningful difference.

The researchers set things up so their participants either knew they’d be exposed to horrible images (such as pictures of injuries and scary animals) or they thought there’d be a chance they might be – this latter condition acted as a simulation of ‘anticipatory anxiety’, like when you have a dentist appointment and you’re not sure if you might need a horrible procedure.

Anticipatory anxiety increased the aversive impact of the images – both in terms of how bad the participants felt after looking at them, and in terms of the electrical activity in their brains, specifically in the beta-frequency range that’s known to be amplified when we’re stressed or worried.

Crucially, however, the effects of anticipatory anxiety on subjective feelings and brain activity were dulled if the participants engaged in 30 seconds of slow breathing (six seconds in, six seconds out) before the task. In fact, after slow breathing, the participants had lower beta brain activity in the anxiety condition than they had in the non-anxiety condition after normal breathing (two seconds in, two seconds out).

It’s a small study and it’s long established that neuroscience findings can be seductive, so I’m wary of being overly gullible. But I thought the design was clever. It showed that, while anxiety can intensify our difficult experiences, a simple, slow-breathing technique can mitigate these effects.

When I’m going through something stressful, I have a strong urge to think out loud about it with someone I trust. There are probably several reasons I end up feeling better: my listener helps me avoid catastrophic thinking, or reminds me that they have my back if things get worse. But another likely reason is that having the chance to describe a difficult situation in detail – even if you’re just describing it to yourself, as in a journal – invites you to see the full picture, and in many cases, it’s not all bad.

Research by Christian Waugh and colleagues at Wake Forest University in North Carolina underscores this and highlights its potential for helping us manage our emotions. They focused largely on people’s experiences during the COVID-19 pandemic, based on data they collected then. When people reflected on a stressful experience they’d been having, and were prompted to describe six specific elements of the situation, they tended to list at least one that was positive (such as spending more time with family during the pandemic). Having more positive elements in the list was associated with feeling less negative and more positive emotion following the task. Taking some time to elaborate on one of the positive aspects seemed to help people feel better, too.

It can be annoying to be told to ‘look on the bright side’ or ‘find the silver lining’. But personal trials often come with opportunities for growth or self-insight; grief or separation sometimes lead to new connections; and even mundane sources of frustration (a traffic jam, say) can contain small points of pleasure or relief (enjoying a song on the radio that you would’ve missed). Where there are such leavening factors, taking a moment to talk or write about the experience could help us make the most of them.