Why We Can’t Lose Weight (and What to Do About It) | Former FDA Commissioner

The Metabolic Crisis in America

Dr. Kessler begins by candidly recounting his own struggle with weight, which worsened during his intense involvement leading Operation Warp Speed during the COVID-19 pandemic. Despite extensive medical knowledge and prior successful weight loss, he found himself 40 pounds heavier afterward, facing the same challenges many Americans experience. He identifies the root issue not as a personal failure or lack of willpower but as a consequence of a toxic food environment that hijacks our biological drives. Central to his argument is the harmful buildup of visceral or "toxic" fat—the fat stored in the liver, pancreas, and heart—which is metabolically active and causally linked to heart failure, diabetes, stroke, cancer, dementia, and other chronic diseases. This toxic fat epidemic is reflected in alarming statistics: only about 6-7% of Americans are metabolically healthy, and up to 25% may develop heart failure in their lifetime.

Rethinking Addiction

A major paradigm shift Kessler advocates is changing how we view food addiction. Unlike common belief that attributes obesity to personal weakness or moral failure, he explains that addiction is fundamentally biological and deeply wired into the human brain. Drawing on parallels from tobacco addiction, Kessler highlights how energy-dense foods—specifically those high in sugar, starch, and fat—activate the brain's dopamine-driven reward circuits. These circuits generate powerful "cue-induced wanting," where smells, times of day, or environments trigger intense urges that can override rational control. Studies show about 14% of the global population, including children, meet criteria for food addiction, while 60-80% of people find these hyperpalatable foods highly rewarding and difficult to resist.

While pharmacologically distinct from drugs such as heroin or amphetamines, highly processed foods share enough neurological effects with nicotine that quitting or reducing intake can be extraordinarily difficult. This addictive quality, combined with the constant availability and aggressive marketing of ultraprocessed foods, creates what Kessler describes as a "food carnival" that makes overeating near-inevitable for many.

The Role of Ultraprocessed Foods

Dr. Kessler traces the origins of the current metabolic epidemic to changes in the American food system, particularly since the 1940s and 50s when industrial processes allowed the mass production of refined sweeteners and starches derived from corn and other commodity crops. These ingredients, such as high-fructose corn syrup, maltodextrin, and dextrose, are chemically isolated from the natural food matrix and then reassembled into convenient, cheap, and highly palatable products lacking fiber and other nutrients that normally regulate appetite and glucose absorption. The result is ultraprocessed foods that are rapidly digestible, create metabolic chaos via hyperinsulinemia, and promote the accumulation of toxic visceral fat.

Kessler emphasizes that while the soda aisle and snack foods are clear offenders, the problem is much broader, as these refined carbohydrates appear in thousands of products hidden behind long and unrecognizable ingredient lists. Furthermore, the food industry deliberately engineered these products to stimulate reward circuits, in a manner reminiscent of tobacco companies' efforts to manipulate nicotine delivery for addiction. Unlike tobacco, however, regulation of processed food ingredients has been limited and inconsistent.

Challenging 'Generally Recognized as Safe' (GRAS)

One of the most groundbreaking portions of the conversation is Kessler's discussion of his recent petition to the Food and Drug Administration (FDA) challenging the longstanding GRAS status accorded to many refined processed carbohydrates. Since the 1958 Food Additives Amendment, foods and ingredients must have "reasonable certainty of no harm" to be approved, but many additives were grandfathered in under GRAS exemptions based on expert consensus decades ago, before the current obesity and metabolic disease epidemic.

The petition argues that the scientific consensus has shifted since the 70s and 80s when ingredients like corn syrup solids and maltodextrin were deemed safe; today, evidence conclusively links these compounds to obesity, type 2 diabetes, cardiovascular disease, and metabolic dysfunction. Importantly, the law places the burden of proof on industry to demonstrate continued safety, and this has not been done. Hence, these ingredients should no longer be considered GRAS and would require formal FDA reevaluation, potentially redefining the industrial food landscape.

Kessler notes this strategy mirrors the successful tobacco fight, which began with citizen petitions and culminated in regulation, labeling, litigation, and ultimately changing social norms around tobacco use. He sees the same potential for a comprehensive approach that includes industry accountability, policy interventions such as taxation and advertising restrictions, and public education to shift the perception of ultraprocessed foods from benign staples to harmful products.

The Role of New Therapeutics

While systemic changes are essential, Kessler acknowledges the immediate struggle of individuals navigating this toxic environment daily. He shares his experience with GLP-1 receptor agonist drugs, which have proven highly effective for weight loss by modulating gut-brain signaling to increase satiety and reduce appetite. These drugs illustrate that obesity is a biological condition—not one simply solved by willpower—and offer powerful tools for patients.

However, he cautions that drugs alone are insufficient and should be integrated with nutrition, exercise, and behavioral support to sustain changes. Furthermore, the challenge remains that without altering the food environment, many patients regain weight after discontinuing medication. Therefore, treatment must be coupled with broader efforts to transform food availability and quality.

A Path Forward

Kessler closes the conversation with a hopeful yet pragmatic call to action. He stresses that changing the GRAS status of harmful ingredients can catalyze regulatory and legislative momentum, enabling hearings, industry accountability, clearer product labeling, and restrictions on marketing—particularly to children. Public health education must shift the narrative, making unhealthy processed foods socially undesirable as was done with cigarettes.

He urges that these efforts will take time, perhaps decades, as with tobacco, but the opportunity is urgent and unique. With advances in scientific understanding, public awareness, and legal tools now converging, the US has a chance to reclaim its health and turn the tide on the metabolic pandemic.

Ultimately, Dr. Kessler offers a message of empowerment: while it is not individuals' fault they struggle with weight in this environment, they can still take steps to reclaim their health, especially with new medical tools and better access to nutrition and care. But to truly succeed, society must redesign its food system—from farm to fork—and hold industry accountable for the products that have fueled chronic disease.