Many major organizations classify obesity as a disease. However, some experts still debate this classification.

Obesity is a condition that involves an excess accumulation of fat that may impair a person’s health. There has been extensive debate about whether obesity is a disease. However, many organizations — including the Centers for Disease Control and Prevention (CDC) — classify it as a disease.

In the United States, over 40% of adults have obesity.

Certain eating and exercise patterns, as well as a lack of sleep, can contribute to excessive weight gain. Some people may also inherit genes that increase their risk of developing obesity. Addressing these factors can aid weight loss and reduce the risk of secondary conditions such as heart disease.

This article examines further the question of whether obesity is a disease. It also discusses what causes obesity, how to treat it, and more.

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The CDC defines disease as “sickness, illness, or loss of health.” The CDC, the World Health Organization (WHO), and the European Parliament all categorize obesity as a disease.

As with other diseases, obesity has a range of different causes. Some people may develop obesity due to lifestyle factors such as diet and activity levels. Others may develop this condition as a result of a genetic condition.

Other possible causes of obesity may include:

Individuals with obesity store excess adipose tissue — fat cells — that can have serious health consequences. Obesity may lead to:

Defining obesity as a disease allows doctors to make a diagnosis and recommend treatment. Getting early and effective treatment can reduce the risk of developing further health issues.

Learn more about obesity.

Some researchers disagree on defining obesity as a disease. One expert states that people with obesity might not feel empowered by this definition. Not feeling empowered might discourage efforts to make lifestyle changes.

Other researchers have concerns that calling obesity a disease could increase weight stigma. This may have a negative effect on the mental health of people living with obesity.

There is ongoing debate surrounding this topic. However, major organizations are shifting their stance on this subject to reflect obesity as a disease.

The CDC measures obesity through body mass index (BMI).

A healthy adult BMI ranges from 18.5 to less than 25. Individuals with a BMI between 25 and less than 30 fall into the overweight range. The category of obesity includes adults with a BMI of 30 or higher.

There are three different classes of obesity:

  • Class 1 obesity involves a BMI of 30 to less than 35.
  • Class 2 obesity ranges from a BMI of 35 to less than 40.
  • Class 3 is the most severe type of obesity, which includes individuals with a BMI of 40 or greater.

A high BMI may be a sign of obesity. However, a doctor may also use other tests to measure body fat before making a diagnosis. These may include ultrasound, waist circumference, and measuring the thickness of a skin fold.

To learn more about how to measure obesity, people can speak with a healthcare professional.

The causes of obesity can vary widely between individuals. Environment, sleep quality, genetics, and other factors may all play a role in this condition.

Certain patterns of food consumption and exercise can lead to excessive weight gain. Consuming more energy than an individual needs may lead to obesity over time. Not getting enough sleep can also contribute to weight gain.

Genetics can also cause or contribute to obesity. Some individuals may inherit genes that make it easier for them to gain weight. Genetic conditions like Prader-Willi syndrome can also increase the risk of developing obesity.

Finally, underlying medical conditions can increase the chance of excessive weight gain. Hypothyroidism and Cushing syndrome can both cause weight gain. Medications such as steroids or certain antidepressants may also contribute to weight gain.

There are many resources and treatment options available to support individuals with obesity. Some common treatment approaches for obesity include:

  • an individualized weight-loss plan
  • lifestyle changes
  • medications that can aid with weight loss
  • weight-loss surgery

Treating underlying health conditions can also support weight loss among individuals with obesity. To learn more about how to address obesity, people can speak with a healthcare professional.

Learn more about possible obesity treatments.

The following are some common questions about obesity.

Does the CDC consider obesity a disease?

The CDC does consider obesity a disease. Its definition of disease is “sickness, illness, or loss of health.” Under this definition, obesity meets the requirements for the category of disease.

What is the difference between obese and morbidly obese?

The term “morbidly obese” refers to the most advanced cases of obesity. These cases typically involve a high BMI and may also involve additional medical conditions resulting from obesity.

However, doctors have been moving away from the term morbidly obese. Instead, they divide obesity into classes based on severity. Class III obesity is the most severe of these classes.

Can you have excess weight and be healthy?

Some people may not experience serious health effects from having overweight or obesity. However, having overweight can lead to negative health effects over time. It can increase the risk of type 2 diabetes, heart disease, osteoarthritis, breathing difficulties, and certain types of cancer.

Obesity is a condition in which an individual’s body weight is considerably higher than the standard weight range. It may develop due to certain dietary patterns or limited physical activity. Certain conditions, genetics, and some medications can also increase the chance of developing obesity.

While major organizations, such as the CDC and the WHO, consider obesity a disease, there is some debate about whether to classify it as such.

Treating obesity may involve certain lifestyle changes, medications, or even bariatric surgery. Finding the right treatment approach depends on the individual and whether they have any underlying conditions.

To learn more about how to prevent and treat obesity, speak with a healthcare professional.