Obesity: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Obesity?
A primary care doctor, such as a family medicine or internal medicine doctor, often starts care for obesity. You may be sent to providers who specialize in nutrition or weight loss. One example is an obesity medicine doctor, a doctor trained in weight management. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
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 is considered healthy for your height.
Doctors often use body mass index (BMI) to check. BMI measures how much you weigh compared to how tall you are. An adult with a BMI of 30 or more is considered to have obesity. Severe obesity is a BMI of 40 or higher.
Obesity raises your risk for many other diseases and health problems. The risk is higher if extra body fat is carried around the waist.
Symptoms
A large waistline, with more body fat around your belly than your hips, raises your risk for weight-related health problems.
Having a larger body size can make your heart work harder and put extra pressure on your joints. It may increase your risk for many health conditions, including:
- Type 2 diabetes
- Heart disease
- High blood pressure
- Stroke
- Osteoarthritis, a joint condition
- Sleep apnea, a sleep breathing problem
- Pregnancy problems and fertility problems
- Some cancers
Causes and who gets it
Obesity happens over time when you take in more calories than you use up. Your body stores the extra calories as fat.
Many factors affect body weight, including:
- Lifestyle habits, such as eating many high-calorie foods, drinking beverages with added sugar, and sitting a lot.
- Not getting enough sleep, which is linked to weight gain.
- Some medicines, including some for epilepsy, depression, or psychotic disorders, corticosteroids, and some diabetes medicines such as insulin.
- Some health problems, such as polycystic ovary syndrome, Cushing's syndrome, hypothyroidism, depression, and long-term stress.
- Family history and genes.
Your chances are greater if one or both of your parents have overweight or obesity.
How doctors diagnose it
Your provider may ask about your health history. This can include your weight history, past weight-loss efforts, and how active you are. They may do a physical exam.
Your provider may also calculate your BMI and check your waist size. They may order blood tests or imaging tests to check for known health problems and other weight-related conditions.
Treatment
Most often, health care professionals treat obesity by helping you make lifestyle changes. The goal is to lose excess weight safely and keep it off over the long term. Lifestyle changes include a healthy eating plan and more physical activity.
Work with a health care professional to set a goal. Losing 5% of your body weight over 6 months may be a good first goal. Losing even 5 to 10% of your weight can delay or prevent some obesity-related diseases.
You may be referred to a team trained in weight management.
When lifestyle changes are not enough, your provider may prescribe weight-loss medicines. Keep following your healthy eating plan and stay active while taking them.
Weight-loss surgery changes your digestive system to help you lose weight. It is also called metabolic and bariatric surgery. Your doctor may suggest it if your BMI is 35 or higher. Some doctors recommend it at a lower BMI if you have a serious weight-related problem, such as type 2 diabetes or sleep apnea.
When to see a doctor
See a doctor if you think your weight may be higher than healthy for your height. Your provider can tell you what a healthy weight is for you and help you set goals.
Call 911 or go to the emergency room if you have chest pain that lasts two minutes or more, trouble breathing, or fainting. Also go if you have sudden dizziness, weakness, or change in vision.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can check your BMI and waist size and look for related problems. They can set goals with you, follow your progress over time, and refer you to nutrition or weight-loss specialists.
Common questions
Is obesity the same as being overweight?
No. Obesity is a disease that means having too much body fat. Overweight means weighing too much. Both mean your weight is greater than what is considered healthy for your height.
What BMI counts as obesity?
An adult with a BMI of 30 or more is considered to have obesity. A BMI of 40 or higher is severe obesity.
Can losing a small amount of weight help?
Yes. Losing even 5 to 10% of your weight can delay or prevent some obesity-related diseases. For someone who weighs 200 pounds, that means losing 10 to 20 pounds.
When is weight-loss surgery an option?
It may be an option when your BMI is 35 or higher. Some doctors recommend it at a lower BMI if you have a serious weight-related problem, such as type 2 diabetes or sleep apnea.
Sources
- MedlinePlus - Obesity
- NIDDK - Treatment for Overweight & Obesity
- NIDDK - Factors Affecting Weight & Health
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
