
Having an overweight partner could increase your risk of developing diabetes – especially if you’re a man. Men are six per cent more likely to develop type 2 diabetes with every single unit increase in their female partner’s body mass index (BMI).
That’s what at Emory University in Atlanta and her colleagues found when they analysed health data from just over 7,000 people in England.
Back when the data started being collected – around the turn of the millennium – the volunteers had an average age of between 59 and 60, and none had diabetes.
Advertisement
In the years that followed, those that had overweight partners were more likely to develop diabetes. It is well-known that being overweight can increase a person’s risk of diabetes, but this is the first evidence that having an overweight partner can, too.
We tend to form relationships with people of a similar size and shape to us, but we also adopt each other’s habits over time, says Nielson. “We tend to marry people like ourselves.” This means that people who have overweight partners are also likely to be overweight themselves, helping to explain the link between overweight partners and diabetes risk.
Gender effect
However, when the team took each person’s own weight into account, there was still a statistical association in heterosexual couples between a wife’s BMI and a husband’s diabetes risk. A man whose partner has BMI of 30 is 21 per cent more likely to develop type 2 diabetes than a man whose partner has a BMI of 25, for example.
This effect isn’t seen in women with overweight husbands. This is probably because women have a disproportionate impact on a household’s diet, as they tend to be the ones doing more of the grocery shopping and cooking, says Nielsen. For example, women who are overweight are also likely to eat unhealthy foods. If her partner eats these too, this might raise his diabetes risk over and above the effect of his own body mass.
When considering a person who is at risk for diabetes, a doctor should asses their partner too, Nielsen says. “We should stop just considering people as individuals, and realise that diabetes risk is linked to who we’re engaging with,” she says.
Diabetologia
Read more: Childcare and housework are what give women more heart problems