Paring pounds through weight-loss surgery doesn’t just make people feel younger — it may actually rewind genetic signs of aging, according to a small study of obese bariatric patients.
Stanford University researchers found that the chromosome caps known as telomeres, which typically get shorter as people age, actually grew longer in certain people who had gastric bypass surgery.
“If your telomeres get longer, you’re likely to reverse the effects of aging,” said Dr. John Morton, Stanford’s chief of bariatric surgery and president-elect of the American Society for Metabolic and Bariatric Surgery, or ASMBS.
The improvement wasn’t large, only about 2 percent to 3 percent in telomere length, said Morton, who is presenting the study Friday during ObesityWeek 2013, an event hosted by the ASMBS and the Obesity Society.
But the benefit was greatest in those who were sickest — patients who were not only heavy, but also had problems like chronic inflammation and heart disease.
And it was a surprising finding that invites more research about the genetic effects of bariatric surgery, Morton said.
“This is the first study to look at surgical weight loss and telomeres,” Morton said. “We know that surgery has a big effect when it comes to weight, but this is literally at the genetic level. It was nice to see confirmation at least that it would improve.”
The study didn't show that weight-loss surgery smoothes wrinkles or prevents gray hair, of course. But Morton said patients often wind up looking younger. "You do have some actual visual changes beyond weight loss," he said.
The patients were mostly women with an average age of 49 and an average body mass index of 44.3, which is considered morbidly obese. Body mass index is a ratio of height and weight, with a BMI of 18 to under 25 considered normal. A person with a BMI of 44.3 might be 5-feet, 9 inches tall and weigh 300 pounds.
On average, the patients in the study lost 71 percent of their excess weight through gastric bypass surgery, which makes the stomach smaller and allows food to bypass part of the small intestine. Their levels of C-reactive protein, or CRP, a measure of inflammation, dropped more than 60 percent and their fasting insulin levels, an indicator of dangerous metabolic syndrome, declined four-fold, the study found.
But, notably, in patients with high levels of LDL or “bad” cholesterol and inflammation before the operation, their telomeres lengthened, compared to patients with lower levels, Morton said.
That makes sense, said Jerry Shay, a cell biologist at the University of Texas Southwestern Medical Center, who was not involved in the study.
People who are overweight often have dramatically shortened telomeres, Shay said. Those are lengths of DNA tied to proteins at the end of chromosomes, often described like the plastic caps on the ends of shoelaces. Every time a cell divides, the telomeres get shorter, eventually reducing so much that the cell stops dividing, and dies.
That doesn’t mean that the person dies, Shay is quick to add. “The length of your telomeres doesn’t mean you’re going to drop dead, it just means that something’s going on. It’s a biological sensor of the stress and damage that is going on in your body.”
That said, Shay says the new study’s findings shouldn’t be interpreted as if weight-loss surgery is the fountain of youth. A 2 percent or 3 percent increase in the length of telomeres is well within the typical margin of error for the tools used to measure them.
It will take more robust studies and careful documentation to convince him of the effect, Shay said. “I don’t think the answer is bariatric surgery. People need to take responsibility for their own health."
The Stanford researchers say further studies are needed to confirm the effects of weight-loss surgery on telomere lengths — and the direct effects of telomere length on actual health results.