Quantified Self
People who track their behavior
aren’t always better off
By Zeynep Tufekci
I was among the many people excited by fitness trackers and
purchased one soon after they came out. It was fun. Look, 20,000
steps in one day (trip to a new city)! Two nights this week of
uninterrupted sleep and 21 miles walked!
There’s something captivating about numbers, which can
explain the existence of the quantified-self phenomenon—that is,
people who measure many things about themselves. Nowadays a
smartwatch or even just your phone can keep track of a wide vari-
ety of markers, including heart rate, sleep patterns, steps in a day
and even arrhythmias. People who run, swim or bike can measure
their pace, distance covered, calories burned or total exercise time.
A clip on your lapel can monitor your exposure to the sun. And per-
haps warming the heart of every parent who got tired of reminding
their children to “stand up straight,” you can even wear a device
that buzzes you if you slump for more than, say, 15 seconds!
You can even spice it all up with “gamification,” setting up
daily or weekly goals, and the program will award you badges
and play celebratory tunes when you hit them. You can also
up load your data to share with others—perhaps in friendly com-
petition. Meanwhile workplace wellness programs that offer
in centives or discounts on health insurance to employees who
use such tracking devices and meet certain goals are spreading.
Unfortunately, despite some early encouraging studies that
suggested that wearers of such devices were healthier than those
who were not, the first large-scale experimental study, where
people were randomly assigned to wear a fitness tracker, showed
no difference in outcomes. Findings are similarly discouraging
for workplace wellness programs: early research hopefully sug-
gested that they were effective for lowering health care expendi-
tures. But once again, better-designed studies showed practical-
ly no difference in outcomes over time.
What’s going on? In fact, probably something very common.
Early studies for new treatments or devices tend to be observa-
tional: they compare individuals who have chosen to take a spe-
cific action (eat a healthy diet; exercise regularly) with those
who do not. Yet that engenders confounding biases because of
the way people self-select into the groups, a problem that can be
resolved only with true randomized experiments.
Should you sport one anyway? One concern is that these
tracking devices are ... tracking devices. Many also track location,
and they’ve already been invoked in court cases. In one, the un -
fortunate victim’s heart rate spiked significantly and then
stopped while the suspect was with her despite his claims he had
left be fore she died. Solving a murder is good, but it’s easy to
imagine health insurers or employers requiring a certain number
of steps a day or using such health data for making decisions.
When I first got my tracker, I tried to hit 10,000 steps a day. It
felt gratifying when it catalogued 10-plus-day streaks of meeting
my goals. This is called the Hawthorne effect, after experiments
in a relay factory outside Chicago, Hawthorne Works, showed
productivity in creased when the lights were turned up—but also
when the lights were turned down. A change, any change, and a
feeling of being observed seem to put us on alert and better
behavior—but only for a time. The novelty does wear off, and
then we return to our baseline behavior.
Still, could it hurt to know the number? Maybe. Employees
who were offered financial rewards along with a tracker fared
worse after the trial ended and the cash dried up as compared
with those who had never been offered incentives. External re -
wards seem to “crowd out” internal motivations—and once they
go away, we don’t always get the internal motivation back.
When my wrist tracker broke down after about a year, I just
didn’t feel like shelling out for another one. Anyway, even by the
end of the third month, I could pretty reliably guess my steps or
hours of sleep for the day without checking the app. Instead I
took inspiration from people who argue that exercise is also
about the right ecology—individuals in walkable cities get a lot
more than those in suburbia, for example. So I now have a tread-
mill desk at work, and I set things up at home so that almost all
my TV viewing is done on an elliptical. And honestly, I get
cranky if I don’t get some movement in during the day. That
seems to be the best motivation to keep turning those pedals.May 2019, ScientificAmerican.com 85Zeynep Tufekci is an associate professor at the University
of North Carolina School of Information and Library Science
and a regular contributor to the New York Times. Her book,
Twitter and Tear Gas: The Power and Fragility of Networked Protest,
was published by Yale University Press in 2017.THE INTERSECTION
WHERE SCIENCE AND SOCIETY MEETIllustration by Thomas Fuchs
JOIN THE CONVERSATION ONLINE
Visit Scientific American on Facebook and Twitter
or send a letter to the editor: [email protected]© 2019 Scientific American