• Definition
    • Obesity means having too much body fat. It is not the same as being overweight, which means weighing too much. A person may be overweight from extra muscle or water, as well as from having too much fat.

      Both terms mean that a person's weight is higher than what is thought to be healthy for his or her height.

      Weight Loss Myths & Facts

      1. "Crash" diets are best for losing weight and keeping it off.

        1. A. Myth
        2. B. Fact

        The correct answer is myth. Crash diets that severely limit calories aren’t safe or successful. They often don’t have enough vitamins and minerals. Most people who try crash diets overeat again and gain weight back. The safest way to lose weight and keep it off is with regular exercise, smaller portions, and a healthy diet.

      2. Healthy snacks between meals can help people manage their weight by:

        1. A. Keeping their hunger in check
        2. B. Preventing them from overeating at mealtime
        3. C. Both A and B

        The correct answer is both A and B. Some snacks can be bad for the waistline, but not all snacks are equal. Healthy snacks are good for you because they’re nutritious and can make you less hungry between meals. They also can also boost your energy in the middle of the day or when you exercise.

      3. Foods labeled "lite" or "light" will help you lose the most weight.

        1. A. Myth
        2. B. Fact

        The correct answer is myth. The word "lite" or "light" can mean lower calories or fat, but sometimes not enough. There is no set standard for that word. Some of these foods may be reduced in fat but have more added sugar. If a product says "lite" or "light," read the label very carefully.

      4. The most important thing about exercise is:

        1. A. Working out in a gym or health club
        2. B. Doing what you enjoy
        3. C. Making sure you always work out in the morning

        You’re more likely to stick with your exercise program if it’s fun and motivating. It helps to have a clear goal. This might be improving your health, reducing stress, exercising for longer, or being able to buy smaller clothes. Do what you enjoy, whether it’s dancing, yoga, karate, or bowling.

      5. If I’m trying to lose weight, I can’t eat fast food anymore.

        1. A. Myth
        2. B. Fact

        The correct answer is myth. Most fast food is loaded with calories, fat, sugar, and salt -- but you can still try to make healthier choices. Look for fast-food places that offer salads, soups, and vegetables. Choose items that are roasted, grilled, baked, or broiled instead breaded or fried. Split meals with a friend.

      6. This can help you stay on track with your weight loss while eating in a restaurant:

        1. A. Read the menu online ahead of time to find healthier dishes
        2. B. Eat a fewer calories earlier in the day
        3. C. Get extra exercise on the same day
        4. D. Eat a small healthy snack, such as carrots or a small apple, shortly before going out
        5. E. All of the above

        The correct answer is all of the above. If you plan ahead, it is possible to eat out and enjoy yourself while staying healthy. And once you know how to pick the right foods and the right amount of foods, you can eat at almost any type of restaurant.

      7. Obese people don’t try hard enough to lose weight.

        1. A. Myth
        2. B. Fact

        The correct answer is myth. There are many reasons why some people can’t keep weight off. Biology is a big factor. Our bodies have a complex system to help keep weight at a healthy level. Our eating habits are the products of how we were raised, where we live, and many other factors.

      8. Which of the following is NOT a good way to help kids get to a healthy weight?

        1. A. Losing weight yourself, if you need to
        2. B. Constantly telling them they are too heavy
        3. C. Praising them when they make good food choices and are active

        The correct answer is B. Do not punish, tease, or put down children who are not motivated to lose weight. This won’t help them. Praising and rewarding them when they are active and make good food choices will encourage them to stay with it. The best thing you can do to motivate your kids is to lead the way and set a good example.

      9. Weight-loss surgery (bariatric surgery) cures obesity.

        1. A. Myth
        2. B. Fact

        The correct answer is myth. Bariatric surgery can jump start weight loss for obese people. But surgery alone is not a cure for obesity. Weight-loss surgery can train you to eat less, but you still need to watch your diet and exercise after the surgery. Talk to your doctor about whether weight-loss surgery is right for you.

      10. In addition to losing weight, being active and eating healthy can help you:

        1. A. Feel more energetic and less stressed
        2. B. Look better in your clothes
        3. C. Tone your body
        4. D. Increase your self-esteem
        5. E. All of the above

        The correct answer is all of the above. With so many good reasons to maintain a healthy weight, why not start eating better and moving more today? Friends and family can be a great source of support. Ask them to join you on your journey to a healthier lifestyle -- they’ll be glad you did.

  • Alternative Names
    • Morbid obesity; Fat - obese

  • Causes
    • Taking in more calories than your body burns can lead to obesity. This is because the body stores unused calories as fat. Obesity can be caused by:

      • Eating more food than your body can use
      • Drinking too much alcohol
      • Not getting enough exercise

      Many obese people who lose large amounts of weight and gain it back think it is their fault. They blame themselves for not having the willpower to keep the weight off. Many people regain more weight than they lost.

      Today, we know that biology is a big reason why some people cannot keep the weight off. Some people who live in the same place and eat the same foods become obese, while others DO NOT. Our bodies have a complex system to keep our weight at a healthy level. In some people, this system does not work normally.

      The way we eat when we are children can affect the way we eat as adults.

      The way we eat over many years becomes a habit. It affects what we eat, when we eat, and how much we eat.

      We may feel that we are surrounded by things that make it easy to overeat and hard to stay active.

      • Many people feel they DO NOT have time to plan and make healthy meals.
      • More people today work desk jobs compared to more active jobs in the past.
      • People with little free time may have less time to exercise.

      The term eating disorder means a group of medical conditions that have an unhealthy focus on eating, dieting, losing or gaining weight, and body image. A person may be obese, follow an unhealthy diet, and have an eating disorder all at the same time.

      Sometimes, medical problems or treatments cause weight gain, including:

      • Underactive thyroid (hypothyroidism)
      • Medicines such as birth control pills, antidepressants, and antipsychotics

      Other things that can cause weight gain are:

      • Quitting smoking. Many people who quit smoking gain 4 to 10 pounds (2 to 5 kilograms, kg) in the first 6 months after quitting.
      • Stress, anxiety, feeling sad, or not sleeping well
      • Menopause. Women may gain 12 to 15 pounds (5.5 to 7 kg) during menopause.
      • Pregnancy. Women may not lose the weight they gained during pregnancy.
      Childhood obesity
  • Exams and Tests
    • The health care provider will perform a physical exam and ask about your medical history, eating habits, and exercise routine.

      The 2 most common ways to assess your weight and measure health risks related to your weight are:

      • Body mass index (BMI)
      • Waist circumference (your waist measurement in inches or centimeters)

      BMI is calculated using height and weight. You and your provider can use your BMI to estimate how much body fat you have.

      Your waist measurement is another way to estimate how much body fat you have. Extra weight around your middle or stomach area increases your risk for type 2 diabetes, heart disease, and stroke. People with "apple-shaped" bodies (meaning they tend to store fat around their waist and have a slim lower body) also have an increased risk for these diseases.

      Obesity and health

      Skin fold measurements may be taken to check your body fat percentage.

      Blood tests may be done to look for thyroid or hormone problems that could lead to weight gain.

  • Treatment

      An active lifestyle and plenty of exercise, along with healthy eating, is the safest way to lose weight. Even modest weight loss can improve your health. You may need a lot of support from family and friends.

      Your main goal should be to learn new, healthy ways of eating and make them part of your daily routine.

      Many people find it hard to change their eating habits and behaviors. You may have practiced some habits for so long that you may not even know they are unhealthy, or you do them without thinking. You need to be motivated to make lifestyle changes. Make the behavior change part of your life over the long term. Know that it takes time to make and keep a change in your lifestyle.

      Work with your provider and dietitian to set realistic, safe daily calorie counts that help you lose weight while staying healthy. Remember that if you drop pounds slowly and steadily, you are more likely to keep them off. Your dietitian can teach you about:

      Extreme diets (fewer than 1100 calories per day) are not thought to be safe or to work very well. These types of diets often DO NOT contain enough vitamins and minerals. Most people who lose weight this way return to overeating and become obese again.

      Learn ways to manage stress other than snacking. Examples may be meditation, yoga, or exercise. If you are depressed or stressed a lot, talk to your provider.


      You may see ads for supplements and herbal remedies that claim they will help you lose weight. Some of these claims may not be true. And some of these supplements can have serious side effects. Talk to your provider before using them.

      You can discuss weight loss medicines with your doctor. Many people lose at least 5 pounds (2 kg) by taking these drugs, but they may regain the weight when they stop taking the medicine unless they have made lifestyle changes.


      Bariatric (weight-loss) surgery can reduce the risk of certain diseases in people with severe obesity. These risks include:

      • Arthritis
      • Diabetes
      • Heart disease
      • High blood pressure
      • Sleep apnea
      • Some cancers
      • Stroke

      Surgery may help people who have been very obese for 5 years or more and have not lost weight from other treatments, such as diet, exercise, or medicine.

      Surgery alone is not the answer for weight loss. It can train you to eat less, but you still have to do much of the work. You must be committed to diet and exercise after surgery. Talk to your doctor to learn if surgery is a good option for you.

      Weight-loss surgeries include:

  • Support Groups
    • Many people find it easier to follow a diet and exercise program if they join a group of people with similar problems.

  • Possible Complications
  • References
    • Cowley MA, Brown WA, Considine RV. Obesity: the problem and its management. In: Jameson JL, De Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 26.

      Ding SA, Simonson DC, Wewalka M, et al. Adjustable gastric band surgery or medical management in patients with type 2 diabetes: a randomized clinical trial. J Clin Endocrinol Metab. 2015;100(7):2546-2556. PMID: 25909333

      Fitch A, Everling L, Fox C, et al. Institute for Clinical Systems Improvement. Prevention and management of obesity for adults. Updated May 2013. Accessed October 1, 2015.

      Kumar RB, Aronne LJ. Efficacy comparison of medications approved for chronic weight management. Obesity (Silver Spring). 2015;23 Suppl 1:S4-S7. PMID: 25900871

      Kushner RF, Ryan DH. Assessment and lifestyle management of patients with obesity: clinical recommendations from systematic reviews. JAMA. 2014;312(9):943-952. PMID: 25182103

      Mingrone G, Panunzi S, De Gaetano A, et al. Bariatric-metabolic surgery versus conventional medical treatment in obese patients with type 2 diabetes: 5 year follow-up of an open-label, single-centre, randomised controlled trial. Lancet. 2015;386(9997):964-973. PMID: 26369473

      Moyer VA. U.S. Preventive Services Task Force. Screening for and management of obesity in adults: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2012;157:373-378. PMID: 22733087

      Richards WO. Morbid obesity. In: Townsend CM, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders: 2012:chap 15.