Proper hydration is essential for life. Maintaining a healthy body water % improves overall health and keeps you feeling energized and operating at peak performance. Tanita"s new Scale plus Body Fat monitors with Body Water % calculate body water levels using bioelectric impedance analysis (BIA), the same highly accurate method used in all our body fat monitoring products. BIA monitors body water % by sending a safe, low-level electrical signal through the body. Our body water scales are the first of their kind available for in-home use.World"s Best Selling - Since 1992, Tanita has produced professional and consumer body fat monitors / body composition monitors using advanced Body Composition technology, with worldwide sales in excess of 15 million units.