Body Mass Index: Normal vs. Overweight

What does it mean to have a BMI in the overweight or obese range? Experts have a variety of answers. The dietary guidelines established by the Department of Agriculture suggest that even those who are mildly overweight should try to reduce their weight. The National Heart, Lung and Blood Institute (NHLBI) guidelines recommend losing weight only if you also have two other health risk factors. The NHLBI views the following as risk factors:

■ a personal or family history of heart disease;

■ being a male over the age of 45;

■ being a post-menopausal female;

■ a history of cigarette smoking;

■ a sedentary lifestyle;

■ high blood pressure;

■ high LDL cholesterol;

■ low HDL cholesterol;

■ high triglycerides; and

■ diabetes.

The more risk factors people have, the more benefit they are likely to gain from bringing their weight down to a healthier level.

The Department of Agriculture and the National Heart, Lung and Blood Institute agree that reducing one's weight by just 10 percent can improve health. Although many overweight people, once motivated to lose weight, set loftier goals, it's important to recognize that a 10 percent drop in weight is a significant achievement.

Assessing obesity

In diagnosing and treating obesity, health-care professionals make assessments (systematic evaluations). A medical assessment is likely to include a variety of measurements, including height, weight, and waist size. The examination tries to rule out organic causes of weight gain, review health risks, and pinpoint health conditions that could affect or be affected by a weight loss.

A psychological assessment screens for mental health disorders that may prevent or complicate successful weight loss efforts. A mental-health professional is likely to look for signs of depression, post-traumatic stress disorder, anxiety, bipolar disorder, addictions, binge-eating disorder, and bulimia.

A nutritional assessment focuses on current eating patterns, weight gains, and dieting history. It also lists all supplements or diet products that the individual may be taking and how ready and willing he or she is to lose weight. Like the psychological assessment, the nutritional assessment may identify factors that might interfere with a successful weight loss - such as physical limitations, time constraints and knowledge of nutrition.

Finally, a health-care professional will assess one's level of physical activity and motivation to increase that level. When someone is motivated to exercise and finds activities that he or she enjoys, weight loss and improved health is faster and easier to achieve.