Question

1. Why do we use indicators to determine obesity?
2. What are some of the characteristics of good indicators?
3. What are the pros and cons of using BMI?

Answer 1

Question :

1. Why do we use indicators to determine obesity?

Answer

Overweight and obesity are well-known risk factors for a wide range of chronic non-communicable diseases, debilitating conditions, and psychosocial problems .The prevalence of overweight and obesity in youth is increasing rapidly worldwide and is a serious concern for public health. Several studies suggest that overweight early in life is associated with increased cardiovascular risks in adulthood .

Abdominal obesity has emerged as an important predictor for adverse health effects; it has been linked to the metabolic syndrome, type 2 diabetes and increased cardiovascular and metabolic risks in both adult men and women . The Body mass index (BMI) is recommended by the World Health Organization (WHO) as the most useful epidemiological measure of obesity. Nevertheless, it is a crude index that does not take into account the distribution of body fat, resulting in variability in different individuals and populations .

The BMI is used as an indicator of overall adiposity, whereas waist circumference (WC) has been advocated as an indicator of abdominal obesity because it is a good predictor of abdominal fat and is related to the development of cardiovascular diseases, type 2 diabetes mellitus, and premature death.

Question

1. What are some of the characteristics of good indicators?

Answer

Ideally, an obesity classification system would have the following characteristics: it would be based on a practical measurement widely available to providers regardless of their setting; it would accurately predict health risk (prognosis); and it could be used to assign treatment stategies and goals. The most accurate measures of body fat (the major component of body weight responsible for adverse outcomes) such as underwater weighing, dual-energy x-ray absorptiometry (DEXA) scanning, computed tomograpy (CT), and magnetic resonance imaging (MRI) are impractical for use in everyday clinical encounters. Estimates of body fat including body mass index (BMI, calculated by dividing the body weight in kilograms by height in meters squared, or kg/m2) and waist circumference do have limitations compared to these imaging methods, but still provide relevant information and are easily implemented in a variety of practice settings.

Question

1. What are the pros and cons of using BMI?

Answer

CONS

The BMI formula is so simple, it's easy to use by just about everyone. However, it's that simplicity that makes it inaccurate because it only takes into account your height and weight. Whether you're overweight or not requires much more information than just your height and weight.

Here are all the things that this BMI formula can get wrong:

• How Much Muscle You Have: The more you have the higher your BMI will be, even though you may be healthy
• Frame Size: A person with a big frame will have a higher BMI, although he or she may still be healthy
• Gender: At the same BMI, women will usually have more body fat than men
• Age: At the same BMI, an older person will usually have more fat than younger adults
• If You're an Athlete: At the same BMI, athletes will usually have less body fat than people who aren't athletes.

• If you're very muscular, pregnant, or have a large frame, your BMI calculation may show you as overweight or obese, even when you're not.

PROS

• Simple, quick, effective and applies to adult men and women, as well as children
• A useful tool for quickly assessing weight classification.
• More accurate at approximating degree of body fatness than weight alone