Body Composition as a Predictor for Chronic Disease
Updated: Sep 12, 2018
Although many people may still be a slave to the scale, I believe the pendulum is beginning to shift in terms of looking at other measurements to determine an individuals risk for chronic disease. The truth is the scale only tells a small part of the story when it comes to health. Another common tool used as a general predictor for healthy weight is the BMI or body mass index which takes into account your height and weight to determine if you are healthy, overweight or obese. The major flaw with the BMI is the inattention to the amount of muscle tissue an individual may have, so often very athletic people may be put in the overweight or even obese categories based on their weight on the scale, not taking into account that muscle is a more dense tissue than fat.
A better predictor for general health and increased risk for chronic disease would be an assessment of body composition or an individuals body fat percentage. There are several methods for assessing someone's body composition which include, but are not limited to, hydrostatic weighing, DXA (Dual energy x-ray), skin fold calipers, bioelectrical impedence, and basic circumference measurements. Depending on the setting some of these methods are more practical than others to implement and they tend to range in terms of their accuracy. For instance, the "gold standard" for body fat measurement is the hydrostatic weighing ("dunk tank") which measures water displacement when the subject is submerged, however this requires a performance lab and can be a costly method of measurement. The same can be said for DXA. Skin fold calipers are a more accurate method of measurement outside the lab and in a less private setting often the bioelectrical impedence and circumference measurements are the less invasive methods. Although the circumference measurements will not give a body fat percentage, a change in measurements will indicate a change in body composition.
Once body fat percentage has been established it is important to understand what is considered a healthy range vs. an unhealthy range. Carrying a higher percentage of body fat can have a number of adverse effects on your health, such as increased risk for heart disease, stroke and diabetes. Excess body fat can also make mobility more challenging and create more work for the joints, thus often resulting in a breakdown of soft tissue surrounding the joints (particularly in the lower body). Everyone needs some fat on their body for normal function of vital organs, however men have a lower essential body fat measurement (3-5%) than women (8-12%) based on the fact that women need more fat for proper hormone production and function of reproductive organs. The outline below will give you a better understanding of the categories associated with body fat percentage for both men and women.
6-13% 14-20% Athletic
14-17% 21-24% Fitness
18-24% 25-31% "Average"
25% + 32+ Obese
If you are interested in having your body composition measurements assessed please see a fitness professional, or inquire about performance labs in your area that may have the equipment necessary for testing.