By way of background: for Christmas last year, I got a Fitbit One, about which I’ve already written an initial review. I’ve been using it daily now for seven weeks, and I thought I’d write something more detailed about how it has affected the way I think about my health and lifestyle, tracking devices, and the idea of a Quantified Self. I’ve also written before about my hesitance about society’s general willingness to abdicate responsibility for self-awareness and owning decision-making about health and well-being to doctors.
The QS movement aims to bring about greater understanding of one’s self and one’s health as a result of data, data, data. The most “traditional” type of self-tracking is dieting, of course, and at its core, the Fitbit is based on this model: it is interested in how much you move, how many calories you are burning, and how many calories you are eating. The sleep tracker moves a step beyond this, looking at data relevant to mental health and wellbeing, energy levels, etc. The Fitbit website allows one to track moods (and allergies!), as well as heart-rate, BP and blood glucose levels (provided you have the appropriate kit at home), but the app does not, limiting the flexibility and responsiveness of the tracking experience that the Fitbit offers.
Tracking one’s diet is quite valuable, I think. Although the protein/carb/fat mix of your daily intake is important, the more critical thing to track seems to me to be the levels of vitamins and minerals you eat on a daily basis, and the food databases within these sorts of apps (the Fitbit’s, MyFitnessPal, etc.) are patchy at best at giving this information. Even if they do, what sort of accuracy can there be, really, when using these average figures? The same goes for the calories in your food, even assuming that you can accurately measure everything, even assuming that calories-in-versus-calories-out is meaningful (it’s a very blunt instrument). (There’s a nice LifeHacker post about this issue and how best to go about keeping track of weight/body measurements, but it remains imperfect.)
I think this basis of generalisation is a real problem for the sort of low-level self-tracking that the Fitbit represents. Even one’s weight is not fixed. It will vary throughout the day, and throughout the month (for both men and women!) as hormone levels vary. So when do you weigh yourself in order to say that you have lost weight or not? Most of the mechanisms that we have available to measure lean-mass versus fat (e.g. weighing scales or skin-fold callipers) are also liable to a relatively high degree of inaccuracy. The closest I think that one can get is actually measuring the body with a measuring tape, although it’s easy for there to be random errors here, too, by holding the tape slightly tighter one time versus the next, or slightly further down one’s chest/waist/thigh.
So given these frustrations, what’s the point?
Well, there is a certain attractiveness to merely having the data. It can act as further motivation — whether your weight/measurement/body fat rises or falls — and it can help to maintain a focus on health that might otherwise get lost in the maelstrom of day-to-day life. It is nice to feel that you’ve done the best that you can on a certain day, and be able to identify where you might improve for another, provided the data does not become ‘law’, affecting beyond reason how you think about yourself.
I’m going to keep using my Fitibt (along with the MyFitnessPal and Sleep Cycle apps), and I’m toying with the idea of paying the £40 pa in order to access Fitbit Premium, which gives you more data that can be compared with the large number other Fitbit users. This element of big data is attractive, and might be worth it, but I haven’t quite decided yet. If I do go for it, rest assured that I’ll be writing about it here!