Is that tracker on your wrist hurting more than helping? Researchers have found that people might be prone to using the positive information they’re receiving as “permission” to eat more.

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On Nutrition

Are you giving too much power to your fitness tracker? In theory, exercise can help you prevent weight gain and possibly help you lose weight, and wearing a fitness tracker will certainly help you monitor how many steps you take, and may nudge you to take more steps than you were before. However, several studies have found that fitness trackers don’t help us move enough to lose weight or even improve health.

Results of a two-year weight-loss intervention study involving 471 young adults, published last September in the Journal of the American Medical Association, found that one group of participants who were randomly assigned fitness trackers lost less weight — about five fewer pounds — than another group that did not use trackers. Both groups improved their fitness and activity levels about equally — so the trackers didn’t make a difference there, either. Researchers said participants may have used the information that they met their activity goals as “permission” to eat more than they would normally.

Another recent study supports the idea that seeing how many calories we’ve burned can influence how much we eat. A study published in December in the journal Appetite had participants exercise enough to burn about 120 calories — but randomly told each participant that they had burned either 50 calories or 265 calories. The participants were given chocolate chip cookies after exercising, and guess who ate more? That’s right, the “265 calories burned” group.

The irony is that many people who slip a fitness tracker on their wrist or clip it to their waistband don’t need the devices — they are already exercising plenty. If you aren’t, simply knowing how much you’re moving may not help you move much more. When a tracker does provide motivation, it wears off pretty quickly — survey data show that 1 in 2 individuals who start using a tracker stop using it within about a year. Information alone can’t help someone overcome long-standing habits like hitting the snooze button instead of the gym, or settling on the couch instead of going for a walk.

Even though trackers may not be a reliable tool for weight loss, for some people they may still be a good tool for increasing physical activity and improving fitness — worthy goals in and of themselves. Here are a few tips for deciding if a tracker is right for you, and how to make the most of it:

• Know yourself. Are you the type of person who gets overly obsessive when you start tracking anything? This can actually be counterproductive to both mental and physical health. Do you get enough activity but enjoy choosing what and how much to do as the spirit moves you? Using a tracker might feel oppressive. However, if you enjoy having an objective measure of how much you’re moving, then you might benefit from a tracker.

• Gather baseline data. Using a tracker for a short time can help you quantify your current level of physical activity, before deciding what new activities to add.

• Set and measure goals. Tracking your daily steps won’t help you increase them if you don’t also set reasonable, progressive goals. Keep in mind that the oft-cited “10,000 steps” is an arbitrary number that has no evidence to back it up. Depending on where you are starting from, that may be too much, or too little, to shoot for.

Finally, a little food for thought: Privacy safeguards for data collected from fitness trackers is notoriously weak. Your personal data is being transmitted to tracking companies, and data is a valuable commodity.