What Does Your Sweat Say About You?

Are you bored with your activity tracker? Do you need something new to inspire your exercise? Or have you ever simply wondered what your sweat says about you? We’re in the same boat, and we’re in luck.

Researchers at Northwestern University have developed a “soft, flexible microfluidic device” that will stick to your skin and measure your sweat. It can tell you how your body is reacting to your workout. It can also tell you if you need more water or other nutrients or even if something more serious is going on. In the future, it could be a key element in diagnosis of some diseases.

The patch is only barely bigger than a quarter. Sweat is captured in tiny compartments in the device, then reacts with chemical reagents, which visibly change the colors on the patch to show the reaction. The colors indicate pH levels and concentrations of glucose, chloride and lactate. It also measures sweat loss and sweat rate. The device interacts with a smartphone so the user can interpret the data. When the phone is near the patch, an app opens and analyzes a photo of the patch, and reports the data.

It’s only meant for one-time use of a few hours, but that’s enough to catch my attention. I have long wondered about the differences in the composition of my sweat from day to day (I know I’m a bit of a geek), so this is fascinating to me. Not to mention, the battery in my activity tracker went out two weeks ago, and I haven’t missed my daily step data enough yet to resolve this issue. Some of my apathy may be due to Thanksgiving, but either way, I’m feeling burnt out on my standard activity tracking right now. I love data, but I’m a little bored. This “lab on the skin,” as the researchers are calling it, has inspired me to work up a sweat again.

No word yet on when we can get our hands on these, but one article on the study says the researchers’ current goal is to make this a cheap, disposable commercial device that will cost just $1 or $2. L’Oreal was one of the main supporters of the research, so I’m hoping that means accelerated availability.

What do you think? Are you interested in your sweat? —Megan