Department of Electrical and Software Engineering, University of Calgary, Calgary, AB T2N 1N4, Canada.
Sensors (Basel). 2021 Oct 20;21(21):6949. doi: 10.3390/s21216949.
Hydration is an important aspect of human health, as water is a critical nutrient used in many physiological processes. However, there is currently no clinical gold standard for non-invasively assessing hydration status. Recent work has suggested that permittivity in the microwave frequency range provides a physiologically meaningful metric for hydration monitoring. Using a simple time of flight technique for estimating permittivity, this study investigates microwave-based hydration assessment using a population of volunteers fasting during Ramadan. Volunteers are measured throughout the day while fasting during Ramadan and while not fasting after Ramadan. Comparing the estimated changes in permittivity to changes in weight and the time s fails to establish a clear relationship between permittivity and hydration. Assessing the subtle changes in hydration found in a population of sedentary, healthy adults proves difficult and more work is required to determine approaches suitable for tracking subtle changes in hydration over time with microwave-based hydration assessment techniques.
水合作用是人类健康的一个重要方面，因为水是许多生理过程中使用的关键营养素。然而，目前还没有非侵入性评估水合状态的临床金标准。最近的研究表明，微波频率范围内的介电常数为水合监测提供了一种具有生理意义的度量。本研究使用一种简单的飞行时间技术来估计介电常数，使用在斋月期间禁食的志愿者群体来研究基于微波的水合评估。志愿者在斋月期间禁食和斋月后不禁食时全天进行测量。将介电常数的估计变化与体重和时间的变化进行比较，未能建立介电常数与水合之间的明确关系。评估久坐、健康成年人中发现的水合的细微变化证明是困难的，需要做更多的工作来确定适合使用基于微波的水合评估技术随时间跟踪水合细微变化的方法。
