This post recaps my recent Barcamp Melbourne talk on personal measurement and the Quantified Self movement. Today marks my 77th day of measuring myself, and changing my behaviour accordingly. I've been recording what I eat, where I go, the habits I keep and those I let lapse. All of this, in aid of a more pragmatic understanding of how I operate as a person, and what makes me happy. Despite all this, I still feel like I'm in an early stage of this experiment.

Food and weight

My weight's bounced around a bit in the last few years. The Hacker Diet, a view that only net energy surplus or deficit will lead to weight loss or weight gain, resonates with me. You can only really work out your net energy for the day by recording what you eat and how much you exercise. It was time for me to get healthier, so record I did.

I first tried this some years ago. Then, I used Calorie King, a site with nutritional information for common Australian foods and energy expenditure for many types of exercise. Still, the book-keeping required was phenomenal and couldn't last. This time I'm using the iPhone app EasyDietDiary, and I'm finding it much easier: Food lookup is snappy, and the phone's camera serves as a barcode scanner for common products. Calorie King also has an iPhone app now, ControlMyWeight, but I was keen to try something new. For personal measurements, I use Dayta, a general data logging app.

I keep a daily energy budget of 7 MJ, and over time I've stuck to it more than I've binged. My metrics for success are my body weight, body fat percentage, and waist circumference. Over these 77 days I've lost 10 kg, reduced my body fat from 24% (borderline obese) to 18% (borderline fit), and shrunk 6cm around the waist, taking me out of an at-risk category for diabetes. In other words, the book-keeping's paid off in spades.


Our location over time reveals a lot about us. It reveals how we commute, how much time we spend at work, how and when we exercise, which friends we see, and how we interact with the city we live in. I started logging mine with the hope that eventually I'd better understand all these things.

Fortunately, today's smartphones come equipped with GPS, so logging location easy and automatic. I started having Google Latitude on my iPhone silently log my location in the background, but it turns out that background updating does not use GPS. Instead, I now use Latify in "driving mode" for much more frequent and accurate GPS updates. This eats battery, but I've become used to charging my phone more often to compensate.

Google Latitude itself provides some limited statistics in its dashboard, such as how much time you spend at work and at home, and how far you've travelled overall. So far, measuring location hasn't changed my behaviour, but I have plans. I'd love to generate a fog of war overlay for Google Maps to highlight areas of my home city Melbourne that I frequent and encourage me to explore beyond them.


A number of daily activities fall into what I'd call habits, things that initially take effort but I'd like to make so routine that they're almost automatic. For me, this includes meditation, cleaning the kitty litter, preparing food rather than takeout, walking or cycling to work, and performing a simple gratefulness exercise each day.

I keep track of these habits using an app called Lift, literally a list you check items off each day. Over time this list becomes a record of what you committed yourself to, and of whether you're honouring these commitments. There's a social aspect too, where people give each other kudos for achieving their daily goals, but I don't use it. For me, this data's still too personal.

Checking myself whether I've completed daily goals definitely helps me achieve them -- in this case measurement changes behaviour. What's lacking is evaluation of the goals themselves. In most cases, I found my goal was a proxy for some other outcome I really wanted. I meditate to reduce stress and improve mood; I exercise to maintain fitness and reduce risk of back pain; I perform a gratefulness exercise since it's known to improve mood. The missing link is to establish empirically that these habits are achieving the outcomes I want from them.

Notable absences

The most notable measurements that I'm still missing include: my mood, the amount and quality of my sleep, energy levels during the day, and levels of real-life social interaction. These are the missing variables in the complex, interrelated web of personal body chemistry that determines how well I can chase life goals, and how happy I can be whilst doing it.

I have ideas for capturing most of these things: for mood I plan to use MoodPanda; for sleep I've used SleepCycle; and for social contact I could mine my calendar and call logs. Ideally there'd be an app which prompts you to take some quick measurements at a handful of random moments during the day, much as I recall has been used to study flow. This would help build a stronger picture of well-being over time.

Overall sentiments

All this might seem to be a lot of effort, effort that risks me not being really present to enjoy life as it passes. But the most sustained and intensive measurement, that of my food, has also been the most rewarding for me. Most of the other areas are cheap to measure, but still bear an element of faith: collect the data for now, and personal discoveries will follow.

This kind of measurement is like super-personalized medicine. If we as individuals have bodies and minds that differ, quantifying yourself is being serious about asking: what works for me? Eventually, this kind of measurement and analysis will become so automatic and so routine that it's basically free. I think it'll be especially powerful for tackling chronic health problems. Until then, I hope a strong community forms of individuals willing to measure and share their personal findings for common good.