Additionally, the research reveals that men – but not women – gain weight in the first few years after becoming a parent.
Study co-author Dr. Joanna Syrda, of the School of Management at the University of Bath in the United Kingdom, and colleagues say that their findings help to shed light on the social factors that could lead to weight gain, which may help individuals to avoid becoming overweight or obese.
The study was recently published in the journal Social Science & Medicine.
The researchers came to their findings by analyzing the data of 8,729 heterosexual couples who were part of the 1999-2013 Panel Study of Income Dynamics, which was originally launched to study family income.
As part of the study, couples were required to provide information on their marital status, body mass index (BMI), and offspring. Data were collected every 2 years.
Married men 3 pounds heavier
The researchers found that, compared with unmarried men, men who were married had a higher BMI, weighing around 1.4 kilograms (3 pounds) more.
Parenthood also appears to affect BMI; the weight of married men increased in the first few years after becoming a father.
However, just prior to and after getting divorced, the researchers identified a reduction in men’s BMI.
The BMI of married women was not influenced by marriage or parenthood, the researchers report.
The team notes that previous studies have suggested that individuals who are single but who are looking for a partner tend to focus more on their fitness than people who are married. They believe that their results support such findings.
Furthermore, the researchers believe that their study strengthens the hypothesis that married people eat richer, more unhealthful foods as a result of greater social engagement.
However, the results oppose studies suggesting that married people are in better health as a result of greater social support from their spouses.
Being mindful after marriage
While further studies are needed to gain a better understanding of how marriage affects weight, the team believes that the current study offers some insight.
“It’s useful for individuals to understand which social factors may influence weight gain, especially common ones such as marriage and parenthood, so that they can make informed decisions about their health and well-being,” says Dr. Syrda.
“For married men who want to avoid BMI increases that will mean being mindful of their own changing motivation, behavior, and eating habits,” she adds.
“Given major public health concerns about obesity, understanding more about the social science factors that can cause weight fluctuation is important.”