HARRISBURG, Pa. (WHTM) — The battle against obesity used to be measured in decades, and it was a losing battle: Ways to fight obesity proliferated, but Americans kept gaining weight.

But drugs are helping people lose more than 15 percent of their body weight, and the trend is emerging suddenly. How suddenly?

“Definitely within the last 6 to 9 months as we’ve seen different therapies that are available to help treat this chronic disease,” said Dr. Fatima Cody Stanford, who teaches at Harvard Medical School and is an obesity medicine physician at Massachusetts General Hospital.

The breakthrough drug is Wegovy, which the FDA approved in 2021 to fight obesity. Wegovy, in turn, is a higher-dose version of Ozempic, which was approved to fight type 2 diabetes but which doctors noticed also caused significant weight loss.

“The weight-loss drug landscape has really changed with the introduction of Wegovy,” said Dr. Charlie Seltzer, a Philadelphia-based internist who specializes in obesity.

Seltzer said obesity results largely from pathways in the brain that cause many people to eat more than their bodies require combined with the availability of tasty, unhealthy food.

“If you lived in the desert in Africa or the jungle in South America, it wouldn’t be a big deal,” he said. “But given the exposure we have to hyper-palatable, high-calorie foods, it’s really, really challenging.”

So how does Wegovy work?

“This class of medication works on the central pathways in the brain that regulate food intake,” Stanford said. “They tell us to eat less … and to do that on a consistent basis. So these medications are working specifically on that pathway.”

She said Wegovy isn’t for everybody — not for pregnant women nor for people with a personal or family history of thyroid cancer, for example. And they’re not without side-effects — nausea is by far the most common, with 44 percent of Wegovy users experiencing at least some nausea. And some doctors have advised stopping doses for as long as three weeks before undergoing anesthesia for surgery to avoid rare but dangerous aspiration.

But Stanford and Seltzer said for most people suffering from obesity, the risk-reward equation favors taking the drugs. So why do only a minority of people suffering from obesity take them.

Because of scarce supplies and high costs, Stanford said. She said Wegovy costs about $1,400 per month, and Medicare, Medicaid and many private insurance policies don’t cover it — a decision she criticized as shortsighted, because she said not treating obesity results in other costly ailments such as heart disease and strokes.

“I want to be able to treat those who look like me, that come from backgrounds like mine,” said Stanford, who is Black. “And in many situations, I’m not able to — not because I don’t want to, but because the coverage may not be equitable.”

Even newer drugs currently in clinical trials show signs of causing even more dramatic weight loss of between 22 and 24 percent, on average, Stanford said.

Another drug, Mounjaro, already approved for diabetes treatment but not yet only for weight loss, has caused weight loss in line with the results experienced by people who take Wegovy.

Still, Stanford said drugs in general remain the second most effective treatment for obesity, behind surgery — the most common is sleeve gastrectomy. She said many patients benefit most from a combination of interventions.

The connection between new treatment and the fall of Jenny Craig weight-loss centers, which filed in May for Chapter 7 bankruptcy protection in the U.S. after nearly 40 years in business?

“If we look at things like Jenny Craig, it really hyper-focused on lifestyle and behavioral strategy — something the person needed to do to ‘fix themselves,'” Stanford said.

The American Medical Association recognized obesity in 2013 as a chronic disease.

“What I love about my job is that I get the privilege of deleting diagnoses from patients’ charts as I treat their obesity,” Stanford said. “I see those other related diseases often fade away.”