Twenty years of nudges, no movement: the CDC data behind the GLP-1 spending decision

The CDC's measured survey found no meaningful change in the share of US adults with obesity between 2013 and 2023, with the age-adjusted rate at 40.3 percent and age-adjusted severe obesity climbing from 7.7 percent to 9.7 percent over the same stretch ^[1][2][3]. That flat decade is the real backdrop to every GLP-1 coverage decision now landing on employer benefits committees and health system formularies, because it is the decade in which the cheaper option was tried.

The cheaper option was not nothing. According to a Vox Future Perfect essay by a writer who has covered obesity on and off for more than 25 years, the period included calorie counts on menus, soda taxes in some places, workplace wellness programs, a small library of funded diet research, campaigns against food deserts, farmers' market promotion, and repeated public advice to eat less and move more ^[4][5]. The author's summary of the outcome is that the lines just kept going up ^[6]. On the measured numbers, severe obesity rose two percentage points, roughly a quarter in relative terms ^[7].

This is not a vanity metric. One demographic model cited in the piece estimated that obesity was associated with roughly 18 percent of deaths among Black and white Americans ages 40 to 85 between 1986 and 2006 ^[8], and the essay describes obesity as the delivery system for other diseases, from diabetes and kidney failure to heart disease and sleep apnea ^[9].

The apparent inflection is in self-reported data, and it comes with caveats the source states plainly. A Gallup report published in July put the US adult obesity rate at 36.4 percent, down from a 39.9 percent peak in 2022, a fall of 3.5 points ^[10][11]. Over roughly the same window, the share of adults saying they were currently taking a GLP-1 drug for weight loss went from 3 percent in 2024 to 11 percent in 2026, approximately 29 million people, close to a fourfold increase ^[12][13]. Vox notes this is correlation only, and that Gallup's self-reported height-and-weight series should not be compared directly with the CDC's measured rate ^[14].

What will actually move coverage decisions is the indication list, not the scale. Semaglutide was first developed and approved for type 2 diabetes, with the higher-dose obesity product, Wegovy, arriving in 2021 after appetite and weight effects showed up in diabetes work ^[15]. Since then: two year-long trials put 469 people with sleep apnea on tirzepatide and cut breathing interruptions by more than half, with roughly half the group ending the year with no apnea or so little that daytime fatigue resolved ^[16]. A trial of 3,533 people with type 2 diabetes and chronic kidney disease, followed a median of 3.4 years, found semaglutide reduced a composite kidney and cardiovascular death endpoint by 24 percent and all-cause mortality by 20 percent ^[17]. In 800 biopsied liver patients, inflammation cleared in nearly 63 percent on semaglutide against 34 percent on placebo at 72 weeks, in a trial still underway ^[18]. In 407 adults with obesity and moderate knee osteoarthritis, WOMAC pain scores fell 41.7 points against 27.5 on placebo ^[19].

Two things to watch. First, whether the CDC's measured series eventually confirms Gallup's direction, since the self-reported drop is the only evidence of reversal on offer ^[10][14]. Second, the framing shift: each organ-specific result moves these drugs from a weight-loss exclusion toward a medical indication, which is the argument that gets budgets opened. The source material carries no price, adherence, or discontinuation data, and the longest follow-up cited is a 3.4-year median ^[17] - so the cost side of the case remains unbuilt here.