Approximately seven in 10 U.S. adults track a health indicator for themselves or for a loved one, although most are just keeping track in the heads, according to new research published by the Pew Research Center's Internet & American Life Project.

The telephone survey of 3,014 adults found that 60 percent track weight, diet or exercise routines and 33 percent track other health indicators or symptoms, such as blood pressure, sleep patterns or headaches. A total of 69 percent track some health issue for themselves or others, but of those health trackers: 

• 49 percent say they keep track of progress “in their heads.”
• 34 percent say they track the data on paper, like in a notebook or journal.
• 21 percent say they use some form of technology to track their health data.

Half of trackers (49 percent) say they update their records or notes only occasionally, when something comes up or changes; half (46 percent) say they update on a regular basis. Thirty-four percent of trackers say they share their records or notes with another person or group, either online or offline. Of those, half (52 percent) share with a clinician.

Not surprisingly, trackers who do not take formal notes are less likely than others to say they update their records on a regular basis or to share their progress with someone else.