At the 28th World Congress of the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO 2025), Marianela Aguirre Ackermann, MD, presented that limited awareness, stigma, and time constraints during consultations prevent internists from discussing metabolic and bariatric surgery with patients, leaving the vast majority of individuals with obesity without appropriate care.

Aguirre Ackermann is a specialist in diabetes and internal medicine at the Endocrinology, Obesity, and Nutrition Center (Centro CIEN) in Buenos Aires, Argentina.

Speaking with Medscape’s Spanish edition, Aguirre Ackerman highlighted The Lancet Commission’s framework, which distinguishes “preclinical” from “clinical” obesity, as a tool to bridge the gap between consultation and surgery.

“It provides a clear definition and emphasizes the health impact of excess weight,” she stated.

“A cultural shift is needed; we need to look at the patient differently. In other words, the patient is no longer a scale, no longer an excess of kilograms, but rather an excess of adiposity that can cause disease,” she said.

Beyond BMI

Aguirre Ackermann said that practice and even surgical criteria in leading guidelines, including those from the American Society for Metabolic and Bariatric Surgery and IFSO, still based on BMI. BMI is quick but ignores organ dysfunction from excess adiposity.

She presented with a case of a 32-year-old woman with a BMI of 33, advanced fibrosis according to the FIB-4 score, and hypertension. Based on BMI alone, she would be ineligible for surgery; however, she would be eligible according to The Lancet Commission criteria.

“This is an excellent approach, but implementation will be difficult,” said Aguirre Ackermann. She noted that the commission acknowledged the added costs and staffing needs for the extra testing required to evaluate clinical obesity. “We need education, training, and resources.”

Barriers in Practice

In practice, obesity management begins and ends with BMI. “Consultation times are short, and obesity competes with other priorities,” said Aguirre Ackermann. “Fewer than 10% of clinicians use obesity guidelines. And insurance coverage remains a barrier.”

She listed barriers at several levels. For patients: lack of psychological readiness, fear, cost, logistical issues, and reluctance to accept referral. For organizations: gaps in training, poor reimbursement, and limited access to multidisciplinary teams. 

For clinicians, the three main barriers are:

• Limited training in obesity treatment: “Most physicians are not familiar with bariatric surgery because it is not in the curriculum. Even those trained in obesity receive little exposure to the surgical component.”
• Stigma: “An internal medicine specialist who sees a patient with a colon polyp assumes cancer risk if nothing is done. But with obesity, they often see patients as not following advice or not moving enough. The problem is framed as behavior, not biology.”
• Time pressure: “Prescribing a drug is quick. If it causes side effects, you stop it. But explaining surgery, including risks and benefits, takes time that busy physicians with full waiting rooms often don’t have.”

Toward Clinical Obesity

According to Aguirre Ackerman, the Lancet Commission’s new definition of obesity brings internists closer to surgery because it frames clinical obesity as organ or functional damage, not just BMI. 

It provides clinical criteria to identify patients who would otherwise be missed, supports reimbursement discussions with payers, and aligns eligibility with surgical outcomes such as obstructive sleep apnea, metabolic dysfunction-associated steatotic liver disease, and hypertension.

She proposed the following practical checklist of assessments for internists to evaluate clinical obesity.

• Adiposity, assessed by waist circumference, waist-to-height ratio, and waist-to-hip ratio
• Liver disease, evaluated through the aspartate transaminase/alanine transaminase ratio, FIB-4 score, and enhanced liver fibrosis test
• Obstructive sleep apnea, screened using overnight polysomnography
• Metabolic measures, such as blood pressure, glycated hemoglobin, lipid profile, and albuminuria
• Functional limitations, assessed to determine the impact of obesity on daily activities and physical performance

“The Lancet Commission took the first step. It’s a big step. Now we must move beyond BMI and turn barriers into bridges,” Aguirre Ackermann concluded.

Aguirre Ackermann disclosed receiving lecture or research fees from Novo Nordisk, Adium/Lilly, Baliarda, and Johnson & Johnson. 

This story was translated from Medscape’s Spanish edition. 

Time pressure: “Prescribing a drug is quick. If it causes side effects, you stop it. But explaining surgery, including risks and benefits, takes time that busy physicians with full waiting rooms often don’t have.”