ANN ARBOR, Michigan - Ms Eileen Isotalo was always able to lose weight, but always gained it back. Now 66, her first diet was with Weight Watchers at the age of 14. She went on to try one diet after another and bought so many books on weight loss that she thinks she has more than the public library.

In desperation, she finally went to a weight management clinic at the University of Michigan.

She had sleep apnea and aching knees, but could not curb her appetite.

“It’s just this drive to eat,” said Ms Isotalo, a retired interior design coordinator. “It’s almost like this panic feeling when you start craving food.”

“My mental shame was profound,” she said.

Now, though, since she started taking Wegovy, one of a new class of drugs for obesity that was prescribed by her doctor at the clinic, those cravings are gone. She has lost 22.6kg and jettisoned the dark clothes she wore to hide her body.

Her obesity-related medical problems have vanished, along with much of the stigma that caused her to retreat from family and friends.

But like others at the clinic, she still struggles with the fear others will judge her for receiving injections to treat her obesity rather than finding the willpower to lose weight and keep it off.

Yet the drug, she said, “changed my life”.

Dr Susan Yanovski, co-director of the office of obesity research at the US National Institute of Diabetes and Digestive and Kidney Diseases, said Wegovy and drugs like it make this “a very exciting time in the field”.

About 100 million Americans, or 42 per cent of the adult population, have obesity, according to the Centres for Disease Control and Prevention.

For the first time, people with obesity, who faced a lifetime of medical jeopardy, can escape the ruthless trap of fruitless dieting and see their obesity-related health problems mitigated, along with the weight loss.

But there is still the taint.

“There’s a moral component to it,” Dr Yanovski said. “People really believe that people with obesity just need to summon their willpower, and they think that taking a medicine is the easy way out.”

Unlike other chronic diseases, obesity is on full public display, Dr Yanovski said.

“No one looks at you and knows you have high cholesterol or high blood pressure,” she said.

Obesity, she added, “is one of the most stigmatised conditions out there”.

Wegovy and a similar but less effective medication, Saxenda, are the only ones in their class of drugs so far to be approved for the treatment of obesity – others like Ozempic and Mounjaro are diabetes drugs but also spur weight loss.

Novo Nordisk, Wegovy’s maker, reports that doctors in the United States have written about 110,000 prescriptions for the drug. Citing a huge demand, the company recently put its advertising for Wegovy on hold.

“We can’t make enough,” said Ms Ambre James-Brown, a Novo Nordisk spokesman.

Supplies are so limited that the company is only selling the drug in the United States, Norway and Denmark, the company’s corporate headquarters.

Its high list price of US$1,349 (S$1,800) a month puts it out of reach for most whose insurance will not cover it. But increasingly many insurers do.

The drugs have arrived at a time when researchers have documented the risks of obesity and the futility of prescribing only diet and exercise as a treatment.

Decades of studies have consistently shown that very few people can lose excess weight and keep it off with lifestyle changes alone.

People with obesity are at risk for a variety of serious medical conditions, including diabetes, high blood pressure, high cholesterol, sleep apnea and non-alcoholic fatty liver disease, a leading reason for liver transplants in the US.

Losing weight can make some of these complications vanish.

Yet the belief persists – fed by diet gurus, influencers and an industry selling supplements and diet plans – that if people really really tried, they could shed pounds.

So those who take a drug like Wegovy often end up in uncomfortable situations that are influenced by the common view that obesity is a lifestyle choice.

At the University of Michigan clinic there are those like Ms Isotalo whose reluctance to admit to taking Wegovy stems from her conviction that those who take it are often thought to be cheating.

Another patient, though, Ms Katarra Ewing of Detroit, readily tells anyone who asks that she takes the drug. She tried diets, but it was Wegovy that allowed her to lose 41kg.

She came to the weight management clinic after her all-night shift at a Ford factory, ebullient and vibrant, wearing a vivid green sweater. She has more energy now that she lost the weight, her mood is brighter, her high blood pressure gone.

But she discovered an unintended social consequence to weight loss, as many longtime friends fell away.

“Only my genuine friends are left and that’s a very small number,” Ms Ewing said.

Obesity medicine specialists say they are not surprised – they see the same thing after people lose weight with bariatric surgery.

Relationships shift because obesity is such a defining condition. People of normal weight may feel superior to a friend with obesity and that helps define a relationship – until the friend loses weight.

Other friends who themselves have obesity may use the condition as a bonding factor in the relationship. Now that is gone.

Another issue is the drugs’ reputation as vanity medications, which has been amplified by comedians’ punchlines at the Oscars and in other high-profile settings. NYTIMES