Men intuitively know it. When your wife or girlfriend goes on a diet, you go on a diet, too. Now a two-year study has confirmed it.
The partners (mostly men) drawn into a weight-loss program lost an average of 2.5 kg, despite receiving no instructions to lose weight themselves. Those left outside the program lost just 0.4 kg.
A new two-year study followed 231 couples in which one person joined a structured weight-loss program. In half the couples, the partner attended some sessions and learnt how to be supportive, but received no instructions to lose weight.
Most of those partners were men, who lost an average of 2.5 kg, compared with 0.4 kg among partners who stayed outside the program.
Two kilos for being the supportive boyfriend is a decent result. Usually you just end up holding a handbag outside the fitting room.
What the study found
- 231 couples were followed for two years.
- 63% of the supporting partners were men.
- Involved partners lost an average of 2.5 kg.
- Partners outside the program lost 0.4 kg.
- The partners were never instructed to lose weight.
Why?
Couples may keep separate bank accounts, playlists and opinions about Married at First Sight. But they invariably still share a fridge and the expense of food.
Once the shopping changes, everyone’s diet changes. The family block of chocolate is replaced with fruit. Portions shrink. If your partner walks, you probably do too. You may never announce a fat-loss plan, but you are living inside somebody else’s.
Researchers sometimes call this the “ripple effect”. Married men or those cohabitating may know it as eating what is put in front of them.
The study could not confirm exactly what caused the weight loss. Partners involved in the program reported cutting 367 calories a day, compared with 196 among the others, but the difference was not statistically significant. Food diaries also depend on people remembering every snack, which is where science meets the mysteriously forgotten biscuit.
The dieter didn’t do any better
The strangest result belonged to the person who actually signed up.
Earlier findings from the same trial showed participants with partner support lost 2.66 kg. Those who attended alone lost 2.89 kg. Bringing a partner along made no meaningful difference to their result.
The supporting actor lost the weight and walked off with the Oscar. The star smiled bravely from row four.
There is one catch
The partners did attend sessions and learn communication skills.
Still, the result confirms something quietly understood in homes everywhere: diets are rarely individual once two people share the shopping and dinner table. If she goes on a diet, you’ll probably lose weight too. Relationships have produced worse side effects.
