Sweat – it helps to stop the body overheating, it creates unsightly underarm stains on clothing, and it stings when it trickles into a person’s eyes. It also contains a wealth of valuable health and fitness information that scientists are just now beginning to tap into. The stick-on monitor on the unusually sweaty forearm pictured, for example, can detect both the rate and volume that a person perspires as well as the sweat’s acidity (an indicator of hydration state), and its concentration of lactate, glucose and chloride ions, which can detect exercise intolerance, hypoglycemia, and electrolyte imbalance among other things. Each of these parameters is detected via colour changes of specific parts of the patch –the dots and squiggly lines. Thus assessing a person’s sweat is as simple as photographing the patch with a smart phone and analysing the data with image processing software. Never has perspiration been so informative.
Written by Ruth Williams
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.