Obesity is currently one of the most serious health issues in the United States, but it is widely misunderstood.
According to the American Heart Association, nearly 42% of Americans live with obesity. Obesity is a significant risk factor in potentially fatal health issues like high blood pressure, stroke, diabetes, and heart disease.
But obesity and poor health are not always co-occuring – 15% of obese adults are considered metabolically healthy. And many people who experience chronic illness such as high blood pressure and type 2 diabetes are not obese.
So should obesity be classified as a disease or not? The answer depends on how it’s defined.
How to define obesity
The medical community agrees that obesity is a growing health issue that needs to be addressed. But there is an ongoing debate around the classification of obesity that gets in the way of healthcare providers’ ability to effectively care for their patients.
The American Medical Association’s Council on Science and Public Health conducted a yearlong study of the issue at the request of the AMA board, and reached the conclusion that obesity is not a disease.
Their conclusion was based primarily on the definition of obesity as a body mass index (BMI) of 30 or higher. BMI only measures a person’s height-to-weight ratio. Although BMI is a handy shorthand for overall body fat, it fails to accurately identify individuals whose organ function is specifically at risk from excess adipose tissue.
BMI measurements don’t recognize the difference between fat and lean muscle mass, so cannot capture important information about fat distribution that is relevant to disease processes.
Despite the Council’s report, in 2013 the AMA elected to classify obesity as a disease. They confirmed the decision again in 2023 amid continuing controversy.
A different approach
In January 2025, the medical journal The Lancet reported the results of a Commission whose goal it was to develop a new definition and diagnostic criteria for obesity.
Given the limitations of BMI, the Lancet’s Commission uses a more complex definition of obesity that involves multiple measurements of body size (waist circumference, waist-to-hip ratio, or waist-to-height ratio) in addition to BMI to provide a clearer view of a person’s health risk from body fat.
Acknowledging both the existence of healthy obese people and the known role of excess body fat (adiposity) – particularly abdominal visceral fat – in numerous chronic illnesses, the Commission distinguished between obesity as a risk factor for disease (preclinical obesity), and obesity as a stand-alone illness (clinical obesity).
The hope is that this more nuanced approach could lead to more appropriate and effective treatments for patients with obesity.
Social determinants of obesity
Scientifically, our understanding of the role that obesity plays in an individual’s overall health has grown significantly in the last decade. But according to the American Heart Association, there is a gap between what we know about obesity and how health care professionals address it.
Some opponents of identifying obesity as a disease continue to argue that obesity is a lifestyle issue that can be changed through healthy habits, and therefore does not require medical treatment. This reveals more lingering social stigma than science, which has found that obesity cannot always be prevented – and can rarely be reversed – simply by eating less and exercising more.
Sociological factors such as education and income influence an individual’s understanding of fitness and nutrition, as well as their access to healthy food and opportunities to exercise. Other factors, including genetics, stress, poor sleep, pre-existing health conditions and prescription medications can all contribute to obesity.
Although healthy lifestyle choices will always be part of obesity treatment, studies have shown that these other sociological and physiological determinants also play important roles.
Social stigma of obesity
For patients with medically significant obesity (BMI >40), designating obesity as a disease opens the door to improved treatments, and better insurance coverage for those treatments.
Patients and healthcare providers need to understand that individuals living with obesity each have unique health profiles and medical needs that may not be centered around excess body fat. Where obesity is a factor in medical conditions, treatment is not as simple as applying willpower at the dinner table.
But as the American Heart Association points out, the social stigma associated with obesity remains a barrier to appropriate diagnosis and treatment. Recognizing that obesity is more complicated than a person’s exercise and eating habits is an important step to changing the harmful attitudes about it in our society.
Where to seek help
WWMG’s family medicine providers serve as an important guide for maintaining your physical and mental health throughout your lifetime. We care for patients at all ages and stages of health, including those living with obesity. .
For patients who have obesity as well as diabetes, heart disease, or arthritis, WWMG’s primary care and specialty providers offer continuity of care. As needed, they can write a referral to WWMG Endocrinology or our Nutrition & Diabetes Education Specialist for additional patient support and resources.
You and your family deserve the highest quality healthcare available. Request an appointment with a WWMG family medicine provider today.