Body Composition

As a part of staying healthy, it is important to consider your body composition as it is just as important as body weight. Our bodies are composed of many components, which include lean body mass and body fat. Lean body mass consists of muscle, bone, tissue, and vital organs. Body fat consists of adipose tissue distributed throughout the body. It is possible to have a low or normal body weight and a high percentage of body fat. It is also possible to have a high body weight and a low percentage of body fat. A description of the range of body fat measurements may be found here: Please Note: It can be very unhealthy for females to have less than 13 % body fat.

By having your body composition analyzed, you have the basic information that you need so that you may take steps to make positive changes to make sure that you have a healthy percentage of body fat. There are a variety of ways to measure body fat.

One of the of the most common ways to measures body fat is bioelectrical impedence. Bioelectrical Impedence Analyzers (BIA) measures body fat based on the rate at which a low level electrical impulse travels through the body. The slower the impulse travels, the more impedence or greater percentage of body fat a person has. The challenge with assessing body fat using this and other methods is the large variability in accuracy. Hydration levels can also change the accuracy of BIA testing.

The current gold standard in body composition analysis is the Dual-Energy X-ray Absorptiometry (DEXA), a machine that emits low levels of radiation which is used to test bone mineral density and provides an accurate assessment of fat to lean mass.

Hydrostatic weighing, which is performed underwater in a large tank is another excellent assessment, but can be costly and hard to find as hydrostatic weighing tanks are usually located at universities or research institutions.

Body Mass Index (BMI)

BMI is a calculation based upon height and weight to help determine a person’s health risk of chronic diseases such as hypertension and Type 2 Diabetes, and is commonly used in a clinical setting due to its ease of calculating. BMI is also correlated closely with body fat analysis, as the two numbers usually are indicative of each other. BMI is reliable for most people between 19 and 70 years of age except for women who are pregnant or breast feeding, competitive athletes, competitive weight lifters, and chronically ill patients. Generally, the higher your BMI, the higher your health risk. The risk increases even further if your waist is greater than 40 inches for men or 35 inches for women. Normalizing your BMI little by little, even if it is not in the normal weight range, is a worthwhile goal to strive for. By eating a healthy, well balanced diet and by being physically active several times each week, most people can attain a comfortable BMI and body composition that they can live with.

As officers of the Commissioned Corps of the U.S. Public Health Service, it is our responsibility to strive to maintain a healthy body BMI and body composition so we can serve to the best of our abilities in whatever capacity we are called upon.