Wedded folks may not hit the treadmill as often as singletons, but they're sure making healthier decisions in the kitchen, according to new findings.

After amassing the data of 10,226 people from nine different countries, researchers compared the relationship between marital status and body mass index (BMI), and found that couples had a higher BMI than singles, contrary to what another study shows, according to a study published in the journal Social Science and Medicine.

The researchers took data from respondents in Austria, France, Germany, Italy, the Netherlands, Poland, Russia, Spain, and the United Kingdom and focused on potential reasons for weight gain by gathering data on eating behaviors and exercise regimens. While the differences in BMI were slight, they still highlight social effects on health.

“Our findings indicate that couples are not healthier in every respect, as has previously been assumed,” said Jutta Mata, lead author of the study and an assistant professor of health psychology at the University of Basel, in a statement.

A normal BMI is from 18.5 to 25, according to the World Health Organization (WHO). BMI looks beyond traditional notions of obesity, which categorized people as either fat or skinny. BMI also takes into account your height. Being overweight is having a BMI range of 25 to 30, and being obese is having a range from 30 and higher.

The average BMI of the single man in the study was 25.7, with the average married man’s BMI being 26.3. In contrast, the single woman’s average index was 25.1 while the married woman’s average index was 25.6. The average height of a woman in the study was 165 cm (5-foot-5) and the average height of a man in the study was 180 cm (5-foot-11). The study showed a difference of 2kg, which equals to nearly 4.5 pounds difference.

The Centers for Disease Control and Prevention states that nearly 35 percent or 78.6 million U.S. adults are obese. The estimated annual medical cost of obesity in America is $147 billion, with obesity-related conditions including heart disease, stroke, and diabetes. Obesity is greatest among middle-age adults.

However, while the data show that couples have in general a higher BMI index, survey data from the respondents showed that couples bought more regional and unprocessed products and less convenience (fast) food. Married men were more likely than single men to buy organic food. However, that doesn’t necessarily mean that they are healthier, because married men as a whole do less strenuous physical activities, such as play sports.

"That indicates that particularly men in long-term relationships are more likely to eat more consciously, and, in turn, probably more healthily," Mata said.

Source: Mata J, Frank R, Hertwig R. Higher body mass index, less exercise, but healthier eating in married adults: Nine representative surveys across Europe. Social Science and Medicine. 2015.