San Francisco company says it’s developing a new wearable fitness device that will glean health data from a person’s sweat.

Kenzen, a San Francisco-based startup that creates wearable diagnostics, is developing a product that promises to provide real-time feedback on the wearer’s health.

The only thing it needs to measure this data is sweat.

The company’s ECHO Smart Patch is a small, flexible, adhesive patch that connects wirelessly to a monitor to measure the wearer’s vital signs.

Kenzen executives hopes the device will become available online to consumers by the end of the year.

“It continuously measures a wide range of biometrics and gathers reliable data to monitor health, and predict and prevent injuries and avoidable health conditions,” Dr. Sonia Sousa, chief executive officer and co-founder of Kenzen, told Healthline in an email. “Individual physiology varies, but most users begin sweating after approximately 15 to 20 minutes of heavy exertion. The sweat is transported across the ECHO Smart Patch to its sensors, which immediately begin analyzing various biomarker concentrations.”

Experts interviewed by Healthline say the device shows promise, but it will take time for medical professionals to properly apply the data it measures to individuals.

Read more: Get the facts on sweat »

While not as common as blood tests, sweat tests can provide valuable information on a person’s health.

“Lots of things can be measured in sweat and the new technology to do so is interesting,” Dr. Benjamin D. Levine, director of the Institute for Exercise and Environmental Medicine, told Healthline.

Cystic fibrosis, for instance, is generally diagnosed using a simple test that measures salt levels in a patient’s sweat.

Performance labs will also swab athletes before and after a workout session in order to gather data.

Sousa says that sweat contains several biomarkers that can help assess an individual’s health.

“Minerals such as sodium and potassium can be detected, but surprisingly, sweat also holds proteins, hormones, and larger molecules like glucose, lactate, and cortisol, which can be used to measure calorie intake and output, muscle fatigue, and even stress levels,” she said.

“It’s really a way to look at electrolyte balance,” Dr. James Borchers, head team physician for athletics, and director of medical services for The Ohio State University Wexner Medical Center, told Healthline. “Performance and biomarkers and athletes’ health are definitely areas where a lot of people are looking to the future because they don’t want to be invasive and do a blood draw, a finger stick, or something like that, in order to get this information.”

“Blood panels are, and will likely continue to be, the gold standard for full clinical assessment,” notes Sousa. “We believe, however, that people need continuous measurements, in context, in order to get ahead of injuries and adverse health conditions. Drawing blood just isn’t easy, affordable, or convenient. And although not a direct correlation to blood, sweat provides a wealth of information about an individual’s health, is readily available, and can be collected and measured painlessly.”

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The wearable technology industry has been projected to be worth $34 billion by 2020.

Most fitness trackers use relatively simple technology to measure step counts, heart rate, and little else — but that is poised to change.

A Stanford University study, released this month, concluded that wearable biosensors can provide useful health data and “might be used as a diagnostic tool to spot disease early.”

Researchers added that it will take some time before this technology finds its way into the hands of consumers.

Kenzen’s patch, assuming it’s released on schedule, is poised to become one of the first advanced wearable biosensors to become widely available.

Borchers says a sweat-monitoring patch could be useful in a sports context.

“I think it could be applied to, for example, endurance athletes, to look at their performance and their health. Same thing for football players. I do think it could give athletic trainers, coaching staffs, and physicians a lot of information about athletes and their training, and what their needs could be moving forward,” he said.

Kenzen’s team echoes this, focusing on professional and elite-level athletes as an initial go-to-market strategy before trickling down to other athletes and consumers.

The company has partnered with two professional sports team — the National Football League’s San Francisco 49ers as well as FC Dallas of Major League Soccer.

The technology shows promise, but Levine cautions that it will take some time for the health community to properly apply the data.

“Right now, the technology appears to be ahead of the knowledge required to use the information appropriately in making decisions about individual patients or athletes,” he said.

While the technology is still in its infancy, Kenzen has big plans.

“Imagine that you get a notification before you get hurt, sick, or develop a more serious medical condition. Would your behavior change? How much could we save on expensive medical treatments if chronic conditions could be detected earlier? Could coaches and trainers preempt costly injuries by pulling players off the field before they cramp up? Would you have more peace of mind if you could remotely monitor your kids’ or mother’s hydration level?” asks Sousa. “We believe all of these things could soon be a reality, and we’re committed to keeping our users safe. Kenzen’s mission is to predict and prevent avoidable injuries and adverse health conditions — and we plan to do this using a simple little patch.”

Read more: Consumers like wearable technology but worry about data security »