Should I Wait to Get Body Composition Analysis Until I'm Done with My Diet?

Feb 14, 2020 1:10:55 PM Posted by Iowa Radiology


white tape measureIf you’re thinking about undergoing body composition analysis (BCA) to understand how to better manage your health, you may be tempted to shed pounds before getting on the scanning table. It can be most effective, however, to have BCA before beginning a diet and exercise regimen, while you’re in the midst of it, and after you’ve reached a goal. A detailed analysis of the proportions of fat, muscle, and bone in your body can serve as a valuable guide for your weight loss planning and help you maintain your results. 


How can BCA help me reach my weight loss goals?


The scale can be misleading.

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.


Body composition analysis helps you put your focus where it’s most needed.

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.

How does DXA BCA work?

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.


Is it dangerous to have repeated X-ray scans?

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.

DXA BCA at Iowa Radiology

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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Armstrong, B. Is BMI an Accurate Way to Measure Body Fat? Published June 22, 2019. Accessed February 7, 2020.
Chen A. If BMI Is The Test Of Health, Many Pro Athletes Would Flunk. Published February 4, 2016. Accessed February 7, 2020.
Diabetes: Body fat percentage, not BMI, predicts risk. Medical News Today. Published April 23, 2018. Accessed February 7, 2020.
DXA/DEXA beats BMI: Using an X-ray Exam to Measure Body Composition & Fat Loss. Published October 29, 2015. Accessed February 7, 2020.

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