Obesity means having too much body fat. It is different from being overweight, which means weighing too much. The weight may come from muscle, bone, fat, and/or body water. Both terms mean that a person's weight is greater than what's considered healthy for his or her height.
Obesity happens over time when you eat more calories than you use. The balance between calories-in and calories-out differs for each person. Factors that might affect your weight include your genetic makeup, overeating, eating high-fat foods, and not being physically active.
Obesity increases your risk of diabetes, heart disease, stroke, arthritis, and some cancers. 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.
Eating more calories than you burn in daily activity and exercise — on a long-term basis — can lead to obesity. Over time, these extra calories add up and cause weight gain.
But it’s not always just about calories in and calories out, or having a sedentary lifestyle. While those are indeed causes of obesity, some causes you cant control.
Common specific causes of obesity include:
BMI is a rough calculation of a person’s weight in relation to their height.
Other more accurate measures of body fat and body fat distribution include:
Your doctor may also order certain tests to help diagnose obesity-related health risks. These may include:
A measurement of the fat around your waist is also a good predictor of your risk for obesity-related diseases.
Obesity can lead to more than simple weight gain.
Having a high ratio of body fat to muscle puts strain on your bones as well as your internal organs. It also increases inflammation in the body, which is thought to be a risk factor for cancer. Obesity is also a major risk factor for type 2 diabetes.
Obesity has been linked to a number of health complications, some of which can be life threatening if not treated:
If you have obesity and been unable to lose weight on your own, medical help is available. Start with your primary care physician, who may be able to refer you to a weight specialist in your area.
Your doctor may also want to work with you as part of a team helping you lose weight. That team might include a dietitian, therapist, or other healthcare staff.
Your doctor will work with you on making needed lifestyle changes. Sometimes, they may recommend medications or weight loss surgery as well. Learn more about treatment for obesity.
There’s been a dramatic increase in obesity and in obesity-related diseases in the last couple decades. This is the reason why communities, states, and the federal government are putting an emphasis on healthier food choices and activities to help turn the tide on obesity.
On a personal level, you can help prevent weight gain and obesity by making healthier lifestyle choices: