What is a recommended preparation step for patients before undergoing a DXA scan?

• A. Avoid exercise for 48 hours
• B. Instruct to take calcium supplements
• C. Avoid calcium supplements for 24 hours
• D. Eat a high-protein meal

Answer: (C)

Avoiding calcium supplements for 24 hours before a DXA (Dual-energy X-ray Absorptiometry) scan is recommended because calcium can influence the results of the scan and lead to inaccurate bone density measurements. High levels of calcium in the bloodstream or system may temporarily increase the density seen in scans, leading to potential misinterpretation of bone health. Therefore, instructing patients to refrain from taking calcium supplements helps ensure that the DXA results reflect their true bone density and are not artificially elevated.

In contrast, advice to avoid exercise is less relevant, as most patients can perform their regular activities without affecting their scan results. Suggesting calcium supplementation before the test could also lead to inaccurate readings, as elevated calcium levels would disrupt the baseline evaluation of bone density. Lastly, recommending a high-protein meal prior to the scan does not directly relate to improving the accuracy of bone density measures and may not have a positive impact on test results.