We live in a “fitness-positive” moment, and the Fitbit is rapidly becoming its accessory of choice. For decades, Americans became increasingly sedentary. The U.S. is notoriously the fattest and laziest nation on earth, the most reliant on cars, the most in love with televisions and game consoles. We invented couch potatoes, drive-through fast food, and the Doritos Locos Taco. Although we’ve long been the poster country for excess, increasingly it seems we’re getting off our behinds and embracing exercise — and now we’re harnessing that formidable technological ingenuity to help us achieve our fitness goals.

I met recently with three friends. As soon as their Fitbits “recognized” each other, our conversation shifted: Who beat her husband in an intra-family Fitbit competition? Who had the highest daily walking average? As the only non-Fitbit-wearer, I was amused to observe how the devices temporarily hijacked our lunch. My iPhone tracks the steps I walk and flights I climb, but unlike a Fitbit, it doesn’t communicate with me proactively, so it doesn’t really change my behavior.

Soon after, I got an email from a friend wondering what to do about her 12-year-old’s pleas for a Fitbit. I went to a trusted source for questions like this: my husband, who treats patients with eating disorders in his psychiatry practice.

I already knew his opinion on Fitbits in general. For people prone to eating disorders, they can be problematic. They give those inclined to over-exercise a new tool with which to monitor themselves, tempting or encouraging them to push themselves even harder. But what about giving these devices to children, who are generally too young to have eating disorders? Or who may have them but it’s not obvious yet?

Fitbits for children are right in line with our fitness-positive, pro-technology culture. Kids want them because they see adults with them, because they’re cool new devices, and because they are on the cutting edge of wearable technology. Most of all, they want them when their friends have them. Meanwhile, many parents hope the devices will encourage children to be more active. After all, obesity is a disease in this country, right?

Ideally, Fitbits help children pay closer attention to their activity levels and develop life-long fitness habits. But I wonder whether Fitbits serve a constructive or potentially destructive purpose? It helps to recall how I felt about exercise at that age.

As a child, I thought of myself as lazy and un-athletic. I disliked competitive sports and I was labeled a non-athlete. Yet when given the chance to ski, dance, ride or do yoga, I participated eagerly. Despite being a firmly committed non-exerciser in college, I now run, practice yoga and do Pilates each week; I feel strong and fit, and not detached from or ashamed of my body the way I did as a teenager.

These changes happened for several reasons. First, I grew up and was no longer a teenager with wildly fluctuating hormone levels and weird growth spurts. Also, I now choose to do the activities I like. I knew I was supposed to exercise as a teenager — I just hated it. External nagging only amplified my internal monologue of self-hatred, and telling a teenager they must do something is the surest way to make sure they won’t. Having a Fitbit or other similar device as a teen would probably only have made me feel worse about myself.

Even if my kids had Fitbits, I don’t know how they could realistically increase their physical activity because of time constraints alone. Children and teenagers differ from adults in that they aren’t fully in charge of their schedules. So wearing a Fitbit isn’t, for example, going to force them to change the way they commute like it might for adults. Most kids can’t realistically opt out of  taking the bus, a car or subway to log more steps. And they can’t not do homework so they can register more activity on their device. My kids don’t have time after school for much physical activity beyond walking home from their bus and sitting down to do homework or go to a music lesson. In the pre-homework era, they spent blissful hours every day running and jumping in the park, but as soon as they began getting homework, we had to stop and come home.

Weekend sports and general activity do help balance out the hours of studying, but I can’t imagine squeezing more time out of the school week to do much else. (Would schools cut down on homework time if they saw how sedentary the homework load forces students to be?)

So would kids, who don’t have the chance to be incredibly active on school nights, then force themselves into more activity on the weekends than necessary? Might this start an unhealthy obsession? And this is the biggest reason to be wary of exercise tracking devices for children — the psychological one.

As my husband reminded me, adolescents are in a particularly vital and impressionable stage in building their identities. They are seeking to define themselves, which is why they sometimes seem to be entirely different people from week to week. When we make a big deal about weight, exercise and body image with children, we open the door for them to build their identities around those goals. This may sound great in theory — who wouldn’t want fitness to be a part of their child’s identity? — but there are real dangers here.

Encouraging fitness and strength has value, but it is challenging to separate those goals from accompanying issues of weight and body shape. Genes are powerful in determining body shape, and adolescents are also going through extreme body changes. Encouraging impressionable kids to consider exercise a “calories in, calories out” activity that can alter their body type is unrealistic and unfair, and the Fitbit plays into that simplistic and inaccurate model. For the child with a predisposition toward over-exercise and eating disorders, this could be a trigger for developing a disorder.

No caring parent would give a child a Fitbit with a malicious motive. But not only might it encourage eating disorders, it also seems simultaneously over-intrusive and detached.

You’re likely still telling yourself that a fitness tracking device is a good idea for your child — the conventional wisdom that exercise is a panacea for body dissatisfaction is strong. But if you really identify a need for more physical activity in your child’s life, try modeling that behavior yourself, or doing more physical activities together as a family. Make exercise about fun and health, not weight loss. Identifying activities your child enjoys rather than relying on a tally of steps taken or distance covered makes building lifelong habits more likely.

Build physical activity into your family’s lifestyle, by all means, but do it the old-fashioned way, and better yet, do it together.

Zanthe Taylor is a writer who lives with her husband and two daughters in Brooklyn. She writes A Million Meals blog and is working on a book about parenting and food. 

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