What is obesity
Last updated: April 1, 2026
Key Facts
- Obesity is a growing global health epidemic affecting over 750 million adults worldwide
- A BMI of 30 or higher is the standard medical classification for obesity
- Obesity increases the risk of type 2 diabetes, heart disease, stroke, and certain cancers
- Contributing factors include genetics, diet, physical inactivity, medications, and metabolic disorders
- Weight loss of 5-10% can significantly improve health markers like blood pressure and blood sugar
Understanding Obesity
Obesity is a chronic medical condition where individuals accumulate excess body fat that negatively impacts health. This is distinct from simply being overweight. Health professionals use Body Mass Index (BMI), calculated as weight in kilograms divided by height in meters squared, as a standard diagnostic tool. Adults with a BMI of 30 or higher are classified as obese, while those with a BMI of 25-29.9 are considered overweight.
Health Complications
Obesity significantly increases the risk of numerous chronic diseases. These include type 2 diabetes, cardiovascular disease, high blood pressure, stroke, fatty liver disease, and certain cancers including breast, colon, and endometrial cancer. Additionally, obesity can contribute to joint problems, sleep apnea, and mental health issues like depression and anxiety.
Contributing Factors
Obesity results from a complex interaction of factors rather than personal failure. Genetics play a substantial role, with some individuals having genetic predispositions toward weight gain. Environmental factors include access to healthy foods, availability of safe spaces for exercise, stress levels, sleep quality, and medications that can cause weight gain. Metabolic disorders and certain medical conditions can also contribute to obesity development.
Treatment Approaches
Weight management typically involves a combination of dietary changes, increased physical activity, and behavioral modifications. Medical professionals may recommend specific calorie targets, portion control strategies, and gradually increasing exercise. For severe obesity, medical interventions like bariatric surgery or prescription medications may be appropriate options alongside lifestyle modifications.
Prevention and Management
Prevention focuses on maintaining balanced nutrition, regular physical activity, stress management, and adequate sleep. Even modest weight loss of 5-10% can improve blood pressure, cholesterol, and blood sugar levels. Successful weight management requires long-term commitment and often benefits from professional support including registered dietitians and behavioral health specialists.
Related Questions
What is the difference between overweight and obese?
Overweight is a BMI of 25-29.9, while obesity is a BMI of 30 or higher. Obesity represents a greater amount of excess body fat and poses higher health risks.
What causes obesity?
Obesity results from multiple factors including genetics, poor diet, physical inactivity, medications, stress, sleep problems, and certain medical conditions. It's typically a combination of these factors rather than a single cause.
How is obesity treated?
Treatment typically involves diet changes, regular exercise, behavior modification, and sometimes medical intervention. Working with healthcare professionals like dietitians can increase success rates.
More What Is in Daily Life
Also in Daily Life
More "What Is" Questions
Trending on WhatAnswers
Browse by Topic
Browse by Question Type
Sources
- CDC - Obesity and OverweightPublic Domain
- Wikipedia - ObesityCC-BY-SA-4.0
- World Health Organization - ObesityCC-BY-4.0