Last Updated December 2021 | This article was created by editorial staff and reviewed by Kyle Bradford Jones

What is obesity?

Obesity is when you weigh more than what is considered healthy for your age, gender, and height. When you’re obese, your body has more (fat) cells, and they’re larger than normal. Obesity can occur at any age. Maintaining a healthy body weight is one of the best ways to avoid weight-related health problems, such as type 2 diabetes or heart disease.

Symptoms of obesity

Common symptoms with obesity include shortness of breath, increased sweating, snoring, and the inability to participate fully in physical activity. It’s a condition that leads to other serious health problems. Each of those health problems has its own set of symptoms.

What causes obesity?

Obesity is often caused by eating more calories than you burn. Calories are the amount of energy in the foods you eat. Some foods have more calories than others. For example, foods that are high in fat and sugar are also high in calories. If you eat more calories than your body uses, the extra calories are stored as body fat. Having too much body fat leads to obesity.

It is also important to note that your body handles calories from different foods in different ways. Calories from sugary foods are more likely to lead to obesity than the same number of healthy calories.

Other causes that contribute to obesity include:

  • Age
  • Genetics (obesity can run in families)
  • Poor sleeping habits
  • Pregnancy
  • Quitting smoking
  • Stress

Some research suggests a link between environment/surroundings and obesity. These can include:

  • Availability of safe and healthy food
  • Availability of exercise options
  • Cleanliness of living space and neighborhood
  • Safe home life
  • Access to medical care

Some medicines and medical conditions can make it difficult to maintain a healthy body weight or to lose weight. Medicines include:

  • Antihistamines, alpha blockers (given for allergies)
  • Beta blockers, methyldopa (given for high blood pressure)
  • Insulin, sulfonylureas (given for diabetes)
  • Lithium (given for manic-depressive illness)
  • Neuroleptics (given for schizophrenia)
  • Progestins (given for endometriosis)
  • Tricyclic antidepressants (given for depression)
  • Valproate (given for epilepsy)

Medical conditions that can affect your weight include:

  • Hormonal disorders
    • Polycystic ovary syndrome
    • Cushing’s disease
    • Diabetes
    • Hypothyroidism
  • Cardiovascular disorders
    • Congestive heart failure
    • Idiopathic hypertrophic cardiomyopathy (disease of the heart muscle)
    • Heart valve disorders
  • Sleep disorders
    • Sleep apnea
    • Upper airway resistance syndrome (blockage of airways during sleep)
  • Eating disorders
    • Bulimia
    • Carbohydrate craving syndrome

Talk to your doctor if you think you have or have had any of the conditions above or take the medicines listed above. In some cases, specific treatments for your medical condition or a change in medicines can make a difference in your efforts to manage your weight.

How is obesity diagnosed?

A person can determine if they’re obese by knowing their Body Mass Index (BMI). This calculates your weight by assessing your age, gender, and height. A BMI of between 25 and 30 is defined as overweight. A BMI of 30 or more is considered obese. You can check your BMI with an online BMI calculator. Simply complete the profile information the calculator requires (age, gender, weight, and height).

Another sign of obesity is the measurement of your waist (belly). An unhealthy body fat distribution around your waist is tied to a number of health issues. You can measure your waist by wrapping a measuring tape around your waist (closest to your belly button). For women, your waist should measure no more than 35 inches. For men, that number is 40 inches.

If you think you might be obese, see your doctor. He or she will talk with you about your eating and exercise habits, your family history, and your overall health. Also, he or she can tell you what you a healthy body weight would be for you.

Can obesity be prevented or avoided?

In many instances, you can avoid becoming obese by eating a healthy diet and exercising regularly. Unfortunately, though, you can’t control some risk factors, such as your age and family history. If your sleep habits are contributing to your obesity, talk to your doctor. If you’re worried that quitting smoking will add to your weight, talk to your doctor about options. Likewise, talk to your doctor about other health conditions, your access to healthy foods and exercises, or medicines that may be adding to your weight.

Obesity treatment

Obesity is treated by losing weight—and keeping it off. Your goal is to lower your BMI to what is appropriate for your age, gender, and height. But losing weight is where most people struggle. Some can do it through healthy eating and exercise, some may need to change their medicines, and some may require surgery.

Your doctor can help you decide what you need and what works best for your circumstances. Start small and set realistic goals. Even losing 10% of your current weight can have substantial health benefits. Small changes can make a surprising difference in your health. Your doctor can offer practical suggestions that don’t require a complete overhaul of your current way of life. In some cases, your physician may refer you to a nutrition specialist. This would likely be a registered dietitian. This person can provide in-depth counseling about food choices.

In some cases, diet and exercise alone may not be enough to help you lose weight. Your doctor may talk to you about prescription weight-loss medicines. These medicines are only helpful when they’re used in addition to healthy eating and exercise.

Your doctor may also talk to you about whether you might be a candidate for weight-loss surgery. Weight-loss surgery (bariatric surgery) can help you lose large amounts of weight if you’re obese. Just as with prescription medicines, weight-loss surgery is most successful when used as part of a long-term healthy lifestyle, including diet and exercise. Some of the more common weight-loss surgeries include:

  • Gastric bypass surgery.During this surgery, your doctor will make a small pouch at the top of your stomach. Your small intestine is then moved from the bottom of the stomach to the new pouch. When you eat, the food that you swallow goes into the new pouch and then into the small intestine, “bypassing” your stomach.
  • Laparoscopic adjustable gastric banding(also called the lap band). In this surgery, your doctor will place a band, like a belt, around your stomach. It separates your stomach into two separate pouches. There is a small passage between the two pouches.
  • Bilipancreatic diversion with duodenal switch (also called a gastrectomy). During this surgery, your doctor will remove most of your stomach. Possible side effects include being unable to absorb all the vitamins and nutrients your body needs. Your doctor will closely monitor your progress after this surgery.
  • Gastric sleeve.In this surgery, part of your stomach is removed, creating less room for food.

Your doctor can explain the different procedures, risks, decide if you’re a good candidate for surgery, and decide on a procedure that would be best for you.

Experts believe you shouldn’t try to lose more than 2 pounds per week. Losing more than 2 pounds in a week usually means that you’re losing water weight and lean muscle instead of losing excess fat. If you do this, you’ll have less energy. And you’ll most likely gain the weight back.

Losing weight is half the battle. Keeping the weight off requires permanent changes to your lifestyle. This includes a healthy diet and exercise. The support of your friends, family, or support group can help.

Living with obesity

If you’re obese, strive to get to a healthy weight because living with obesity can be hard. It will likely mean living with serious health problems, including:

  • Arthritis
  • Cancer
  • Coronary artery disease
  • Depression
  • Gallbladder disease
  • Gynecological problems, such as infertility
  • High blood pressure
  • High cholesterol
  • Metabolic syndrome
  • Stroke
  • Type 2 diabetes

Questions for your doctor

  • I have tried everything to lose weight. Why isn’t it working?
  • What are some healthy food options that are affordable?
  • Where can I find healthy recipes?
  • What can I do to overcome my family history of obesity?
  • What can I do to prevent obesity in my children?
  • Is weight loss surgery right for me? Is it risky?