If your marriage is teetering on the brink, have a flick through your family photo album. Scientists reckon it is possible to predict whose marriages will fail by looking at snapshots taken decades earlier. Those with the brightest smiles, they say, are more than three times more likely to forge a strong relationship than those who frown their way through family outings as a child or teenager.

“Smile intensity predicted whether or not participants divorced at some point in their lives,” claim the researchers, from DePauw University in Indiana. “The less intensely participants smiled, the more likely they would be divorced later in life.'

To make the link, the scientists asked almost 650 adults for pictures taken when they were as young as five and during their final year of school and rated the brightness of their smiles. They then asked the volunteers if they had ever been divorced – and matched their answers with the data on their smiles.

The researchers say they think it may be that people with happy personalities are more likely to try to work through rocky spots in relationships. Alternatively, those with a sunny disposition may marry similarly upbeat souls. It is also possible that happiness is contagious.

Assuming there is a smidgen of truth in the findings, published this week, here’s an idea to try to salvage a failing marriage: In the same way the organisation Relate uses a technique to get couples to fall in love all over again by getting them to act like they’re in love, smiling at your partner – even when your inclination is to glower – could be a way of turning the relationship around.

The expression “smile and the world smiles with you” might be trite, but, as with most sayings, it has some substance. Smiling a lot not only makes you feel sunnier, it endears you to others. If you’re unhappy and frustrated in your marriage, turning on a megawatt smile when your spouse walks into the room isn’t easy, but mustering even a half-beam can make a difference. Everyone wants to be liked and appreciated, so if your partner thinks you’re pleased to see them, they are more likely to feel benign towards you. It’s a lot more difficult to be argumentative or combative if your other half is bestowing a beatific smile upon you.

Learning to smile through the pain is hard, but it can have positive repercussions. And if you want your ailing marriage to succeed, it’s at least worth a try. You may have been a glum as a child, but you can be a beamer now – and it just might save your marriage.