MAY 14, 2026 – Obesity is a chronic disease involving excess or dysfunctional body fat that can affect health. It’s influenced by complex biological, behavioral, genetic, and environmental factors that impact hunger, fullness, metabolism, and body weight.
In people with obesity, excess or dysfunctional body fat can lead to other health issues. The systems that control hunger, a feeling of fullness, metabolism, and body weight don’t work the way they should, according to a revised Department of Defense and Department of Veterans Affairs’ Clinical Practice Guideline for the Management of Adult Overweight and Obesity. The guideline discusses how tackling obesity can be accomplished through a personalized treatment approach designed to keep warfighters healthy and lethal.
Clinical practice guidelines are evidence-based tools, enabling primary care providers of service members, beneficiaries, veterans, and their families to stay up to date on current science — ensuring the medical force is as ready as the warfighters they treat. Guidelines are continually updated to include the latest research and best practices, delivering integrated DOD-VA capabilities, including clinical care standards. The revised obesity guideline was published in November 2025.
The previous revision in 2020 already described overweight and obesity as chronic medical conditions requiring long-term management, said Cmdr. Elizabeth Bauer, a U.S. Navy endocrinologist, obesity specialist, and clinical associate professor of medicine at Naval Medical Center San Diego.
“The 2025 update builds on that prior framing and more explicitly describes obesity as a chronic, relapsing, multifactorial disease requiring individualized, long-term management,” she explained.
Why your body resists permanent weight loss
People with overweight or obesity do not simply lack willpower. While moving more and eating fewer calories is a foundation for weight loss, their bodies can work against them to restore their previous weight. It’s called the “set point,” Bauer said.
Your body has biological mechanisms that defend against weight loss, she said. These mechanisms can persist even when people take the right actions to lose weight and can contribute to regaining weight over time. “Your set point can cause your body to increase hunger hormones, decrease satiety hormones that make you feel full, drop energy expenditure, and increase your desire to eat food,” Bauer explained.
“These changes are not temporary. Studies show these hormonal shifts persist for at least 12 months after weight loss and likely much longer, creating a sustained biological drive to regain the lost weight,” said Bauer.
Additional factors that affect long-term weight management
Genetics can also influence body weight and response to treatment, said Dr. Richele Corrado, a doctor of osteopathy in internal medicine, obesity medicine specialist, and clinical associate professor of medicine at the Uniformed Services University, Bethesda, Maryland. She and Bauer were the two DOD co-champions on the working group that revised the CPG.
“Up to 70% of physical and psychological traits can be inherited,” said Corrado. “Your genes can play a role in determining whether your body wants to store or burn calories. In someone who is genetically predisposed to calorie storage, it’s challenging to avoid weight gain in our modern-day obesogenic environment,” a setting made up of physical, economic, and sociocultural factors that promotes high energy intake and sedentary behavior. “Those individuals may need treatments like medications or surgery to reduce the neurohormonal drive toward calorie storage and thus weight gain,” Corrado said.
Mental factors also affect weight loss. “Obesity and mental health conditions can influence one another through overlapping biological and social pathways, including chronic inflammation, stress-related hormones, sleep disruption, weight stigma, and brain circuits involved in appetite, reward, and mood,” Corrado explained.
Daily duties and deployments increase the risk factors for warfighters, she said. These risk factors include irregular sleep schedules, irregular meals, and constant high stress and alertness levels.
Weight stigma can also affect health and treatment engagement
“In society, we’ve been taught that you should be able to control your weight on your own,” said Corrado. “Now we know the biology is complex, and it may be challenging to manage on your own.”
For people with overweight or obesity, “stigma and bias can worsen their disease because they may feel dismissed or unfairly judged for their weight within the healthcare system,” she said. “This negative characterization can contribute to stress, unhealthy coping behaviors, worsened mental health, delayed or avoided medical care, and poorer health outcomes overall.”
Personalized treatment options
The revised CPG recommends a personalized approach to weight management therapy, starting with a comprehensive history, physical examination, and assessment of obesity-related complications to help doctors determine appropriate treatment options. A tailored weight-loss approach, adapted for all warfighters of past, present, and future, is key to success, the new guideline emphasizes.
“You can have two patients with the exact same BMI (body mass index). One can have no obesity-related complications, and the other has three, because it depends on where the excess fat is distributed in the body and not just weight itself,” Bauer said. “Personalized care is crucial for accurate diagnoses, an effective plan of action, and a comprehensive lifestyle program.”
Bauer said the CPG addresses the evolving role of GLP-1-based therapies and other obesity medications, including their weight loss, weight maintenance, and improvement in obesity-related complications.
Maintaining healthy weight takes a lifetime
People with overweight or obesity may need long-term support to improve and maintain health.
“The key to successful and healthy weight loss requires a comprehensive approach,” #_msocom_1#_msocom_2said Corrado. “An obesity medication can make you feel like you aren’t as hungry. But if you’re not eating good-quality foods, you may not be healthy despite losing weight. You may still have high blood pressure, or high cholesterol, or fatty liver, or cardiovascular disease risk”. However, obesity medication typically makes it easier to eat smaller portions, snack less, or make a better food decision.”
“This is why the revised CPG emphasizes that many patients need to combine lifestyle changes with medications or surgical interventions that can counteract these biological defenses,” said Bauer.
She stressed: “It’s not a failure of willpower, it’s physiology, and we now have tools that work with the body’s biology rather than against it.”
CPG and Military Health System resources
· Patient summary
· Provider summary
· Provider pocket card
· Trends in the prevalence of obesity among U.S. active component service members and civilians
· Consortium for Health and Military Performance: The Uniformed Services University tool provides holistic approaches to optimize warfighter and family readiness through information on human performance research.
Story by Janet A. Aker
Defense Health Agency