TUESDAY, May 28, 2013 (HealthDay News) -- Weight-loss operations in women could be a genetic bonus for the health of their future children, a new study suggests.
Researchers found differences in the activity of genes in children born to women after they'd had gastric bypass surgery compared to their siblings born before surgery. The changes suggest that the kids born after surgery, to thinner mothers, will fare better in terms of heart health because of benefits gained in the womb.
"It appears that there's an effect that is transmitted to the next generation," said study co-author Marie-Claude Vohl, a professor at Laval University in Quebec City. "This may have some consequence later in life for the health of the children."
The study isn't definitive, and researchers don't know exactly how much the health of kids may be affected by being born to a thinner mother. It's also not clear if there's something unique about weight-loss surgery or if the key is to simply drop pounds.
Weight-loss surgery, which aims to limit the amount of food that patients can eat, is no simple matter. It's expensive, involves risk and is not always covered by insurance. However, severe obesity is itself a major health risk.
In the new study, researchers examined the genetic makeup of 50 children who were born to 20 mothers before or after they underwent gastric bypass surgery.
The researchers suspected that the genes of children born after surgery would act differently than those born before. They found several thousand genes that did just that, and the differences in the post-surgery children suggest they're in better shape health-wise.
As far as physical differences, children born to mothers before weight-loss surgery weighed more and had greater waist and hip girth compared to the others. Children born to mothers after weight loss-surgery had better fasting insulin levels and lower blood pressure.
"It's more evidence that the benefits of gastric bypass surgery extend beyond the original aim of weight loss," said Dr. Francesco Rubino, a metabolic and bariatric surgeon with the Catholic University of Rome, who was not involved with the study. Other research has linked weight-loss surgery, in some cases, to major improvements in diabetes.
What's going on? It's not a matter of the mothers transferring different genes to the children based on whether they'd had surgery. Instead, weight-loss surgery seems to affect the activity of the genes in the children's bodies even outside the womb, he said.
Dr. Edward Phillips, vice chair of the department of surgery at Cedars-Sinai Medical Center, in Los Angeles, said it's a mystery how that might happen.
"If you're a fetus, you're bathed in a bunch of chemicals and hormones," Phillips said. "But when you're out in the real world, why wouldn't your own genes go back to the basic set of what they were supposed to be?"
Could weight-loss surgery in fathers have a similar effect on their subsequent children? Researchers don't know. There are other questions too. Might the children born after their mothers had surgery be exposed to a different kind of environment than their older siblings, especially in regard to food? Could that affect how their genes act?
Phillips said those questions need to be answered. But, he said, this is still "an exciting early study" that opens the door toward greater understanding of genes and weight.
The study appeared online May 27 in the Proceedings of the National Academy of Sciences.
For more about gastric bypass surgery, try the U.S. National Library of Medicine.