Alex Ehsan, MD, PhD · Medical search

Obesity

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

What is obesity?

Obesity is a disease that means having too much body fat. It is different from being overweight, which means weighing too much. Both terms mean that your weight is greater than what's considered healthy for your height.

Body Mass Index (BMI) measures how much you weigh compared to how tall you are. An adult who has a BMI of 30 or more is considered to have obesity. Severe obesity is having a BMI of 40 or higher. Obesity increases your risk for many other diseases and health problems, especially if the extra body fat is carried around the waist.

What raises your risk of obesity?

Obesity happens over time from taking in more calories (through food and drinks) than used up from physical activity and daily living. Your body stores the extra calories as fat. The right balance between calories and activity is different for everyone.

There are many different factors that can affect your body weight. Certain medicines or medical conditions may affect your weight. Other factors include your:

How is obesity diagnosed?

To find out if you have obesity, your health care provider may:

What health problems can obesity cause?

Having a larger body size can make your heart work harder, put extra pressure on your joints, and may increase your risk for many health conditions, including:

If you have obesity, losing even 5 to 10% of your weight can delay or prevent some of these diseases. For example, that means losing 10 to 20 pounds if you weigh 200 pounds.

What are the treatments for obesity?

Treatment plans for obesity may depend on your overall weight, other health conditions, and your willingness to participate in a weight-loss plan.

Your provider can tell you what a healthy weight is for you, help you set goals, and give you tips on how to lose weight. They may refer you to other providers that specialize in nutrition or weight loss to help you make realistic goals and provide support.

Possible treatments may include:

A healthy lifestyle that includes healthy eating patterns and regular physical activity can help you lose weight and lower your chance of developing complications related to obesity.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

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