Let them see you sweat

Sweat, ick. It betrays our nervousness, leaves unsightly blotches on our clothes, drips down our faces, and makes us stink. Sure, it cools us when we overheat, but most of the time we think of it purely as an inconvenience. We may soon, however, learn to like our sweat a lot more-or at least what it can reveal about our health. We'd certainly prefer giving a doctor a little sweat to being punctured for a blood test-or even providing a urine sample-as long as we didn't have to run a mile or sit in a sauna to do it. And if sweat could provide constant updates about our bodies' reactions to a medication, or track head trauma in athletes, we might just start to appreciate it. Sweat contains a trove of medical information and can provide it in almost real time. And now you can monitor your sweat with a wearable gadget that stimulates and collects it using a small patch and analyzes it using a smartphone-that is, if you visit my lab.