After weight loss surgery, relationships might change as much as weight: Study

Weight-loss surgery can be life changing -- it can dramatically affect weight and overall health. But, until recently, little was known about how the surgery might change relationships. What researchers found might be surprising.

Bariatric surgery is only recommended for people with severe or morbid obesity and it has been shown to lead to very substantial weight loss, which allows people to restart their lives.

To understand what other effects the surgery might have had on their personal lives, researchers in this study looked at adults from Sweden in two major studies.

The first study included nearly 2,000 adults, 71 percent of whom were women, who had bariatric surgery and compared them to a control group of obese people who did not have the surgery. The second study included nearly 30,000 adults, 76 percent of whom were women, who had gastric bypass surgery and compared them to 300,000 adults in the general population.

For those who were single, having bariatric surgery was associated with an increased rate of marriage and new relationships. But for those who were already in a relationship, bariatric surgery was associated with an increased rate of divorce and separation.

Those who lost the most weight were most likely to have a change in their love lives, according to the study.

However, the research was limited in some ways, including the fact that the study looked at people in Sweden and the results might not apply to people in other places. Additionally, the authors were unable to tell who initiated the relationship changes, the person who lost the weight or their partners.

But the study highlights the fact that changes in weight can affect more than just physical size. As a person's self-confidence and other lifestyle behaviors change with pronounced weight loss and improved health, other aspects of their personal lives can change, as well.

Dr. Hector M. Florimon is a third-year resident in pediatrics at New York Presbyterian-Columbia University Medical Center, working in the ABC News Medical Unit.