Obesity is a chronic (long-term) medical disease whereby the body carries too much body fat. By 2030, it is projected that 1 in 2 Americans will have obesity (defined as a Body Mass Index, or BMI, of >30 kg/m2). Both overweight (BMI >25 kg/m2) and obesity can make it more likely you will develop other diseases. These problems include, but are not limited to, type 2 diabetes, high blood pressure, stroke, fatty liver and more serious forms of liver disease, sleep apnea, osteoarthritis, gallstones, high cholesterol, gout, and certain types of cancer. Obesity can make many other medical problems harder to treat, lead to increased disability, and even raises the risk of early death. Obesity is sometimes associated with stigma, which can affect a person’s mental health, quality of life, and lead to biases in how people with obesity are treated.
Obesity is a very complex metabolic disease and not a problem of willpower or self-control. Having obesity or being overweight is not the patient’s fault, obesity results from a complex biology whereby the body increases the amount of fat it wants to hold on to. As a result, people with obesity may crave more calorie-dense foods and are more likely to store extra calories as fat. The result is weight gain, or more specifically, an increase in the amount of fat the body wants to carry. The reasons for this are not yet well understood but some of the contributors are thought to be unhealthy diet, unhealthy muscle, lack of sleep, disruptions in circadian rhythm, and weight gain-promoting mediations, among others.
Some medications may cause weight gain, such as those used to treat diabetes, psychiatric illnesses, neurologic disorders, or inflammatory conditions. Your doctor may be able to suggest a different medication that has less effect on weight gain.
There are some hormone imbalances that can contribute to weight, such as hypothyroidism (under-active thyroid gland) or Cushing’s syndrome (high cortisol levels). These are uncommon causes of obesity.
The Endocrine Society works to reduce the prevalence of obesity, identify policy options to address obesity, and advocate for access to affordable care.
