Skin temperature as a marker of human health in the Northwest Indian scenario

This study introduces a flexible skin thermometer for personalized body temperature monitoring, enabling continuous measurement and offering advantages over conventional mouth-based techniques that are limited to point-in-time readings. Such personalization is critical for medical applications, particularly in environments with varying climatic conditions. Our in-house developed flexible thermometer FLEXTEM provides continuous real-time temperature readings, can be used on different body sites (such as forehead and forearm), and adapts to diverse physiological and environmental factors. In a novel study involving ∼470 individuals from Rajasthan, a region characterized by extreme seasonal variations, FLEXTEM was tested alongside standard digital and infrared thermometers, to examine the influence of environmental (such as ambient temperature) and physiological (such as gender) factors on body temperature. Based on the findings, normal body temperature ranges were established for different demographic groups based on gender and work conditions. However, defining ranges based on health status was constrained by the smaller sample size. Our research highlights the potential of flexible skin-based thermometers for tailored health assessments and demonstrates how environmental factors can lead to variations in body temperature ranges. • FLEXTEM enables accurate, continuous skin temperature monitoring with 4 sensors; TCR: 0.00275 ± 1.19 × 10⁻⁴/°C, response: 5 s. • FLEXTEM shows strong agreement with standard infrared thermometer (ICC: 0.82 - 0.9); validated via BA and ANOVA . • Body temperature correlates with environment; site workers show higher temperatures. Males show higher underarm temperatures than females.