The following Mark's Daily Apple article was written by Mark Sisson, and is narrated by Tina Lehman.

Should you wear a fitness tracker?

For a nation of supposedly obese, lazy, and sedentary layabouts,

American consumers sure are interested in tracking their daily activity levels.

In 2015, they bought 13.4 million dedicated activity trackers, up 50% from the previous year,

and spent almost 1.5 billion on the devices.

That's in addition to the hundreds of millions of smartphones in circulation that also track

your daily steps, sleep quality and duration, and calorie expenditure.

From Fitbit to Jawbone, to Apple Watch, to dozens of others, the wearable fitness tracking gadget industry is growing quickly.

Venture Capital has responded, pouring billions into the wearable industry.

Are they worth it?

Well, it depends.

According to some data, about a third of users stop using their devices within six months of getting them.

Then again, most people don't know the difference between polyunsaturated and saturated fat.

Most people don't care enough to watch their carbon take or pay a little extra for grass-fed

beef or eat a big-ass salad every day.

These statistics collate yet ignore individual data points. If you decided to pick up a Fitbit

or jawbone or an Apple Watch, the only data point that matters is yours. Most people might stop

using their wearable after a couple of months. You might keep wearing it. Are they accurate?

According to research from December of last year, they aren't

very accurate at tracking data beyond step count. Researchers analyzed 22 studies exploring the

ability of Fitbit and jawbone, the two most popular trackers, to accurately track sleep,

...