The study was reported in the January 2009 issue of The American Journal of Preventive and covered more than 6,000 Australian women. The study followed young women, beginning with ages 18 to 23, over a 10 year period. Surveys were administered on regular period covering an array of questions, including weight and height, age, level of education, physical activity, smoking status, alcohol consumption, medications used and a wide range of other health and health care issues.
The report shows that for women who did give birth, the majority of the weight came after the birth of the first child. Subsequent child births had little impact on the amount of weight gained.
The differences, the scientists found, were stark.
Now here are the results after all variables were taken into account: after 10 years an average 140-pound woman who had a baby and a partner put on 20 pounds; If a women was childless and did not have a partner she put on 11 pounds; and yet, her’s the rub if the woman was childless and had a partner she out on average 15 pounds. In other words having a mate meant 4 extra pounds after 10 years. And while there were women who had a baby with no partner, it number was too small to draw any significant conclusions.
Researchers assumed that there were no inherent metabolic reason why having a partner would cause weight gain, so the presumption is that partnering and weight gain is a behavioral issue. The other mildly depressing fact was there was a steady weight gain over time amongst all women regardless of partnering or relationship status.
While the Australian report focused solely on women, the article cited another study that looked at men who had children – there was an increase in obesity in men as well.
All of which adds to the evidence that social and behavioral issues around partnering and child-rearing leads to life-style changes that are less than healthy. So now there is another risk factor for which we have to be aware: Having a life-partner may include many benefits – but it may make it more difficult to maintain an optimally healthy lifestyle.