While we talk a lot about weight loss, and many health professionals continue to refer to body mass index (BMI), as a measure of obesity, consensus is growing that BMI is an unreliable indicator of whether a person is carrying excess body fat. BMI is a number derived from a person’s height and weight. Looking at this number alone gives us no information about the relative proportions of fat and muscle in the body, often resulting in a distorted picture of a person’s health.
It’s commonly understood that muscle weighs more than fat. So, if you were to gain muscle but lose the same amount of weight in fat, your BMI wouldn’t change. This is why people who are actually quite fit can be classified as overweight or even obese when using BMI as the guiding metric. On the other hand, people with very little muscle mass can have a BMI in the normal range but actually have an unhealthy proportion of fat in their bodies. Body composition analysis using dual-energy X-ray absorptiometry (DXA BCA) provides the most accurate information available about muscle and fat proportions in the body.
If you understand your body composition, you have a better idea of what kinds of actions will be most beneficial for your health. For example, if your BMI is in the normal range but your DXA BCA shows low muscle mass and high fat content, you may decide to focus on strength training with an aim to maintain your current weight while building muscle. Sharing your results with a nutritionist, personal trainer, or other health professional can be an effective way to develop a nutrition and exercise plan to meet your goals.
Dual-energy X-ray absorptiometry uses a low dose of X-rays to create a detailed image that reveals precise information about the proportions of fat, bone, and muscle in each part of the body. You simply lie face up on the table while the machine scans your body. The procedure is painless and noninvasive and is complete in just three to five minutes.
DXA technology uses a radiation dose that is extremely low—just a tenth of the dose used in panoramic dental X-rays and the equivalent of what a person typically absorbs from the natural environment in a single day. The radiation dose from 100 DXA scans is equivalent to that delivered in a single chest X-ray. So, even if you have several DXA scans throughout the course of a weight loss program, you would still be exposed very little radiation as a result.
Iowa Radiology provides a broad range of state-of-the-art imaging procedures, including DXA BCA. The cost is just $49 per scan or $139 for a package of three scans, due at the initial time of service. You can schedule your appointment at our downtown Des Moines or Clive location by calling 515-226-9810. You don’t need a doctor’s referral.
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