I recently wrote a column about wearable computing, in which I discussed a future in which people will eventually wear glasses and contact lenses with built-in screens, delivering content we can use. It will be like having smartphones in our eyes, but much smarter ones.

Researchers I spoke with for my column noted that it would be at least 10 years before Facebook updates were being flashed into our retinas in real time. In the interim, though, the first iteration of wearable computers are here, focusing on tracking people’s health.

“I think we are at the very beginning of wearable computing,” said Julia Hu, founder and chief executive of Lark, a start-up based in Mountain View, Calif., that makes a wearable sleep tracking monitor. “You’re starting to see a lot of sensors that track data and then visualize it.”

She added, “A big part of the first wave of wearables will be personalizing health and more importantly, making the information relevant for people.”

Ms. Hu’s company chose to focus on sleep better because, she said, more than 70 million Americans have a sleeping disorder.

Although people might think the biggest hurdle with wearable computers is the creation of the devices, Ms. Hu said knowing what to do with the data these computers capture was more important. For example, the Lark tracks more than 3,000 micro data points each night through a wrist device users put on before going to sleep. Lark’s software, which runs on a smartphone, then parses through all the micro-motions it has tracked throughout the night and makes recommendations to users.

“We use a type of sleep research called actigraphy — it’s what sleep scientists have used for the last 15 years — and then we sift through your personalized data and offer a better sleep, diet and exercise schedule,” Ms. Hu said.

Michael Liebhold, a senior researcher specializing in wearable computing at the Institute for the Future in Palo Alto, Calif., said in a phone interview that health applications made the most sense for today’s consumer-oriented wearables. Rather than offering health care, he said that new wearable devices were aimed at helping to promote wellness by helping people understand health issues before they became problems.

“We are seeing these wearables that create a health-aware environment, with sensors and devices used to monitor our health and fitness and then giving us visualized feedback of the results,” Mr. Liebhold said. He said this trend would become more pervasive as people learned to tack more sensors onto their bodies.

But one wonders if people will actually wear these devices. Although health promoting and sleep monitoring devices may be useful and responsible, they aren’t exactly sexy products for mainstream consumers. And they won’t allow us to send Twitter messages from our eyeballs.

Still, it’s nice to know they might help us get a good night’s sleep.