Overweight and Obesity

Are you at a healthy weight? You may have your own ideas about what weight is healthy for you, or you may want to talk it over with your health care provider. 

As general guidelines, however, health experts have developed standards that define normal weight, overweight and obesity in adults. Today, approximately 65 percent of adults are overweight or obese. Sixty-one million adult Americans are considered obese. And, about 16 percent of American children are overweight – more than twice the percentage of 30 years ago.

According to the National Institutes of Health (NIH), overweight and obesity are linked to increased risk of heart disease, type 2 diabetes, high blood pressure, certain cancers and other chronic conditions. Maintaining a healthy weight is important to maintaining your health. 

Assessing your risk
According to the NHLBI guidelines, assessment of overweight involves using three key measures:

  • body mass index (BMI)
  • waist circumference, and 
  • risk factors for diseases and conditions associated with obesity. 
The BMI is a measure of your weight relative to your height and waist circumference. Another way of gauging risk measures abdominal fat. Combining these measurements with information about your additional risk factors yields your risk for developing obesity-associated diseases.

What is your risk?

1. Using Body Mass Index (BMI)
BMI is a reliable indicator of total body fat, which is related to the risk of disease and death. The score is valid for both men and women but it does have some limits. The limits are:
  • It may overestimate body fat in athletes and others who have a muscular build. 
  • It may underestimate body fat in older persons and others who have lost muscle mass.
Use the BMI calculator or tables to estimate your total body fat. The BMI score means the following: 
  • Underweight: BMI below 18.5
  • Normal: BMI 18.5 to 24.9
  • Overweight: BMI 25.0 to 29.9
  • Obese: BMI 30.0 and above 

2. Using waist circumference
Determine your waist circumference by placing a measuring tape snugly around your waist. It is a good indicator of your abdominal fat, which is another predictor of your risk for developing risk factors for heart disease and other diseases. This risk increases with a waist measurement of over 40 inches in men and over 35 inches in women. 

The table, Risks of Obesity-Associated Diseases by BMI and Waist Circumference, provides you with an idea of whether your BMI combined with your waist circumference increases your risk for developing obesity associated diseases or conditions.

3. Other risk factors
Besides being overweight or obese, there are additional risk factors to consider:

  • high blood pressure (hypertension) 
  • high LDL-cholesterol ("bad" cholesterol) 
  • low HDL-cholesterol ("good" cholesterol) 
  • high triglycerides 
  • high blood glucose (sugar) 
  • family history of premature heart disease 
  • physical inactivity 
  • cigarette smoking
4. Assessment
For people who are considered obese (BMI greater than or equal to 30) or those who are overweight (BMI of 25 to 29.9) and have two or more risk factors, the guidelines recommend weight loss. Even a small weight loss (just 10 percent of your current weight) will help to lower your risk of developing diseases associated with obesity. Patients who are overweight, do not have a high waist measurement and have less than two risk factors may need to prevent further weight gain rather than lose weight.

Talk to your doctor to see if you are at an increased risk and if you should lose weight. Your doctor will evaluate your BMI, waist measurement and others risk factors for heart disease. Persons who are overweight or obese have a greater chance of developing high blood pressure, high blood cholesterol or other lipid disorders, type 2 diabetes, heart disease, stroke and certain cancers, and even a small weight loss (just 10 percent of your current weight) will help to lower your risk of developing those diseases. 

Source: National Heart, Lung, and Blood Institute, the National Institutes of Health