FASHION FORWARD: The Fitbit Flex Wireless Activity & Sleep Wristband looks as good as it works.

There’s also a social-media component of tracking that allows users to share their data with select friends — or the world — if they choose. Jeff Christman, a freelance TV news producer, linked his Fitbit with friends to see who could clock the most steps each day. “It’s definitely a great way to motivate you to exercise — when you know others are watching,” Christman says.

Though I’ve kept the settings private on my devices and apps — sharing my pathetic step count and proclivity for Swedish Fish candy and ring bologna with others doesn’t interest me — I did send a blood sample to Talking20, a California-based company that allows people to monitor their cholesterol, estrogen, testosterone, hemoglobin, vitamin B12 and other amino acids over time. There is such a demand for the kits — which include a lance, an alcohol swab and a special card on which to deposit the blood and that range in cost from $99 to $1,200 — the company has had to halt sales to fulfill existing orders.

“It’s a sign of the times,” says Talking20 founder Heather Heine, a medical doctor, researcher and entrepreneur. “There’s a big shift happening in personal and preventive health care.”

My results are still on back order, but I have, however, developed a strange sense of responsibility toward the sensors encircling my wrists like parole bracelets. During a trip to New York to visit Dean, I was about to hop the escalator in the train station before catching a flash of my UP band. Not wanting to disappoint it, I took the stairs.

“That’s awesome,” Dean says when I tell him in his Chinatown office. “It’s not about the app or the accuracy of data. What’s important is creating awareness about your level of activity and what you’re putting in your body.”

But it doesn’t happen without effort, especially when it comes to tracking food and beverage intake. Although both the UP and Fitbit have apps that include a large database of meals and snacks with corresponding nutritional and caloric information, I still have to manually input what I eat, a process that takes me between five and 10 minutes, depending on my meal. Salads are especially frustrating, because unless I have a prepackaged concoction or ate at a restaurant whose menu was included in the app’s system, I have to individually record each ingredient. Trying to figure out whether I consumed four or five grape tomatoes and how many tablespoons of balsamic vinaigrette were drizzled on my greens is often an exercise in indigestion. It’s gotten to the point where I’ve stopped snacking (or at least have become more mindful of what I eat between meals), as having to record a handful of peanuts or nibble of chocolate isn’t worth the time.