Height difference in a relationship is the key to happiness, apparently.

Image: Getty.

If you regularly rely on your partner to fetch things from the top kitchen cupboard, you’re about to feel vindicated.

A recent study published in the Journal of Personality and Individual Differences found that the greater the height difference between a couple, the happier the wife was.

While science has long claimed women are drawn to tall men for evolutionary reasons (as it’s associated with strength) the study led by researchers from South Korea is the first to examine how it affects the happiness of the couple involved.

Analysing data of 7,580 people, the researchers found that a greater height difference in a couple was positively related to the wife’s happiness. (Watch: people confess when they knew their partner was the one. Post continues after video.)

While it suggests that it’s a potentially key factor in a happy marriage (alongside respect, shared interests and, you know, love) unfortunately it doesn’t apply infinitely.

The relationship between height difference and happiness gradually weakened over time, before becoming totally irrelevant after 18 years of marriage.

“‘Nevertheless, the long period of the dissipation indicates a powerful impact of male height on women’s psychology, probably prepared by evolution,” concluded researcher Dr Kitae Sohn, of South Korea’s Konkuk University. (Post continues after gallery.)

In his conclusion, Dr Sohn suggested a number of possible reasons to explain why the attraction loses its power over time, such as a wife “getting used to her husband’s height and its correlates such as physical attractiveness and strength.”

As for his other reasons? We’re not quite so sure about.

"She might lose her characteristics that enabled her to marry her tall husband, such as beauty; the loss could cause her unhappiness directly or indirectly by changing her husband’s behaviour, such as showing less affection to her, more affection to other women, and providing less childcare," Dr Sohn wrote.

Right... We think we'll just pretend he didn't say that one.

Whatever the reason, it's good news for couples with significant height differences - and hopefully it makes up for all those times you've struggled to get a photo of the two of you in the same frame.

Is your partner significantly taller than you?