By the 1990s, diet and exercise trends had changed. The “Buns of Steel” fitness video caused a stir and Snackwells took the American supermarket by storm. I remember picking out these squishy, ​​low-fat cookies in plastic trays. They reminded me of chocolate, but only a little.

By the late 1990s, the obesity rate was over 30%.

In the early 2000s, spinning classes swept the country as an effective, sweaty way to burn calories. And dieters have been divided, with some embracing the low-carb Atkins diet and others opting for Dr. Dean Ornish’s low-fat, vegetarian approach.

Somehow, though, all that dwindling breadbasket, Diet-Coke drinking, and butt toning didn’t add up to much. Today, the obesity rate is over 40%. And more than 70% of Americans are at least overweight.

“To me, obesity is the pandemic of the 21st century,” says Andrew Greenberg, director of the Obesity Metabolism Laboratory at the Tufts Center for Human Nutrition Research.

But now we are at a major turning point. Anti-hunger drugs, including Novo Nordisk’s Wegovy and Eli Lilly’s Mounjaro, promise to help Americans lose a lot of weight.

On average, studies show that patients lose 15-20% of their body weight after injecting the drugs for about a year. But we don’t yet know their long-term side effects — or whether paying for them will break the healthcare system.

So how did we get here? How did our diets go so wrong? Can indefinite injections change things? Or do we risk abandoning prevention in favor of prescription?

Our misconceptions about fat

Dr Robert Lustig, a pediatric endocrinologist at the University of California, San Francisco, says we’ve been giving people the wrong advice on diet for 50 years, which is why we’ve failed in our efforts to fight obesity .

In 1977, the Senate offered a series of recommendations on how Americans should change their eating habits, which focused, among other things, on reducing fat intake.

“We were told fat was the problem,” Lustig says. “It turned out to be the worst dietary advice we could have ever received. … People still think low fat is important, including the USDA.

Fats are found to help fill you up, replace other foods (often refined carbs) and, depending on the fat, can have an array of biological benefits.

Lustig, who directs UCSF’s weight assessment for adolescent and child health program, argues the real problem is insulin.

He says insulin increases when we eat sugar and refined carbs, but not fat. This, in turn, promotes insulin resistance and increases the risk of cardiovascular disease. And we eat a lot more carbohydrates than before. Between 1980 and 1997 alone, Americans added more than 400 calories a day of carbs, many of which came from a single source: corn syrup.

Dr. Dariush Mozaffarian, a cardiologist and professor of nutrition at Tufts’ Friedman School of Nutrition Science and Policy, agrees that the focus on a low-fat diet was a huge mistake.

“We had the wrong dietary recommendation for 30 years,” he says. “The food industry is still actively marketing low-fat foods.” He points out that polls show that many Americans (50% in a 2018 Gallup poll) say they try to avoid eating fat.

Mozaffarian says things have gone so wrong for so long — including avoiding fat and embracing highly processed foods — that we may have “changed our physiology as a nation.” We have changed our gut microbiota. We have changed the epigenetics that mothers transfer to their babies.

An Ozempic injector.RYAN DAVID BROWNE/NYT

Surprisingly and frighteningly, Americans seem to be eating no more calories today than they did in 2000. However, over those 20+ years, obesity rates have continued to rise. Which led Mozaffarian to wonder if a fundamental – but poorly understood – change has created a “self-perpetuating and hard-to-reverse cycle”.

So, will drugs like Wegovy and Mounjaro change things?

All the doctors I spoke to said they could be helpful. For obese patients, especially those struggling with conditions such as type 2 diabetes, sleep apnea or heart disease, the drugs seem to be extremely effective in reducing weight, which has undeniable benefits. Wegovy and Mounjaro both increase insulin production, building on the knowledge that Ozempic – a drug diabetics have used for years to lower blood sugar – has been prescribed off-label for weight loss. (Wegovy is basically a stronger version of Ozempic.)

Greenberg thinks it’s a very exciting time, in large part because obesity has proven so difficult to treat. His own research on obesity was inspired by the death of his mother following a stroke, caused by type 2 diabetes associated with obesity. And he says the evidence now confirms what every dieter knows: it’s incredibly hard to lose weight and keep it off.

Still, he acknowledges, there are a lot of unknowns with these new drugs, one of which is how patients will react to them over the years. Research indicates that you need to inject the drugs indefinitely to maintain weight loss. And Greenberg says that “there are open questions about long-term security.”

Another unknown is the effectiveness of drugs in reducing disease. And here Lustig is particularly skeptical.

“I’m not against the vaccine,” he says, noting that he prescribed drugs for children who were insulin resistant. But he fears that embracing a new class of weight-loss drugs — rather than fundamentally changing our diets — will “sidestep the issues, address the issues. That’s why all these drugs only reduce weight by 16% and won’t cure heart disease, Alzheimer’s or anything else. … You can’t outgrow a bad diet, and you can’t cure a bad diet any better.

Finally, there is the rather huge question of cost. Wegovy costs about $16,000 a year, so if 100 million people — less than a third of Americans — wanted it, the cost would be $1.6 trillion (the cost of the entire healthcare system was $4.3 trillion in 2021). “We’re going bankrupt,” Mozaffarian says. “It’s just not possible to give the drugs to everyone.”

Of course, many wealthy patients were able to access it, despite production shortages and massive demand. Although wealthier Americans tend to be thinner, that hasn’t stopped some from clamoring for prescriptions.

Dr. Lauren Fiechtner, director of the Center for Pediatric Nutrition at Mass General Hospital, explains that for children, lifestyle interventions – including the provision of healthy foods, nutritional counseling and activity counseling fitness and getting enough sleep – have many advantages over medication. They lead to lasting weight loss, cost less and have a positive impact on siblings and parents. And about 20% of American children are now obese.

But we have a system based on drug approval, not on complementary services. “To scale these [lifestyle interventions] at very high levels, we need insurance reimbursement,” Fiechtner told me. “And it was a real fight.”

Which makes no sense. In the face of an epidemic of unhealthy eating, our current solution is to pay huge sums of money – through taxes and insurance premiums – to correct one symptom of this epidemic: weight.

Of course, new drugs will have a role to play. But truly tackling the problem would require massive investment in prevention.

Sessions with dieticians and community health workers should be affordable and very easy to access, especially for children. The same goes for fruit and vegetable prescriptions, which make the products cheap (or free) to obtain. Avoiding obesity, heart disease and type 2 diabetes is much better than treating them later.

Research shows that having children spend a total of 20 to 30 hours per year with a health care team – a dietitian, community health worker and pediatrician – reduces BMI and improves other measures of health, according to Fiechtner.

But she says Medicaid in Massachusetts will not cover the cost of community health workers. And in rural Mississippi, where she is involved in another comprehensive program, Medicaid will not reimburse dieticians or community health workers.

Why are we saving a penny on prevention, if prevention costs a fraction of what weight-loss drugs cost? What if prevention has benefits these drugs can’t touch?

For 40 years, we have postponed the inevitable. And now it’s here. Pouring money into lifestyle changes is our only hope – and, strangely enough, it’s the cheapest option.


Follow Kara Miller on Twitter @karaemiller.