The attempt to subtype obesity

It’s part of a series about new obesity drugs that are transforming patients’ lives, dividing medical experts and spurring one of the biggest trade battles in years. Learn more about the obesity revolution.

“Anne” sits in a small, wood-paneled consulting room at the Mayo Clinic in Rochester, Minnesota, about to embark on another weight loss journey. Except this one might be different from all the others – the Weight Watchers tours, Jenny Craig and dietitian-led programs. Her doctor, Andres Acosta, probes her fight to a depth that is new to Anne.

Acosta begins today’s appointment by telling Anne — a pseudonym we used to protect his patient’s confidentiality — that he wants to understand the “root cause” of her obesity. An hour-long interview about her life, medical history, and nutrition and physical activity habits follows, along with a quiz about what she thinks might cause her to overeat or indulge in the wrong foods. Food stress emerges as a major theme – but the doctor also notes that her weight piled up after her pregnancies, when she was diagnosed with an autoimmune condition attacking the thyroid, Hashimoto’s disease. She went from being “alarmingly” 120 pounds skinny in college to obese at 41. Now 68 and weighing 183 pounds, her knees suffer from arthritis, which makes walking difficult; she suffers from high blood pressure, obstructive sleep apnea and high cholesterol. The extra weight is not a cosmetic concern; she says it is slowly eroding her health.

At the end of the appointment, Acosta tells Anne about the battery of tests he wants her to undergo next – a thyroid workup, investigations into her emotional eating, and checks on her resting metabolic rate, composition body and its “gastric emptying” (to determine how quickly food empties from its stomach and if this could be a cause of excessive hunger). He suspects that instead of the lack of willpower many people – including clinicians – are still associated with obesity, Anne’s case could be caused by a slow metabolic rate related to her Hashimoto, in combination with her apparent emotional eating. She will need more than the standard “eat less, move more” prescription that many obese patients receive.

With the tailored approach, Acosta tries to reflect a truth that obesity researchers and clinicians have known for years but rarely address in the clinic: obesity is not one thing, it is many. “Obesity is a complex and heterogeneous disease,” Acosta said. The causes of weight gain differ between people, and excess fat is linked to various health consequences – cancer or heart disease in some, type 2 diabetes in others, while still others are spared from metabolic problems.

Yet patients generally receive “one size fits all” solutions — although researchers also know that individual responses to the same weight loss interventions vary widely. Clinical trials of nearly every lifestyle program – from diet and exercise programs to weight loss advice – show that some patients gain weight, some lose a lot, and most cluster around an average unimpressive, often regaining long-term lost weight.