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Quantify thyself: Tracking your life from food to mood

Track your every move, brainwave and bodily function with a new breed of personal gadgets and you could become fitter, healthier and happier, finds Nic Fleming

Quantify thyself: Tracking your life from food to mood

IT IS a few minutes before midnight and I am pacing around my living room in circles. My wife appears at the top of the stairs looking concerned. Glancing at the display of a small black box attached to my belt, I tell her that I鈥檒l come to bed soon. I need to reach 15,000 paces. She is not placated.

No, I haven鈥檛 lost the plot. I have temporarily joined ranks with a growing number of people who measure many aspects of their lives, often in minute detail. Leading the charge is the Quantified Self movement, and they want to know whether all this information could be useful, helping them to lose weight, become fitter or even anticipate medical problems.

Like it or not, you may soon be joining them. What鈥檚 on offer is just too compelling: recording our activities and mining the resulting data could make us healthier and happier. But does it live up to the hype?

Until recently, gathering detailed personal data involved a visit to a lab, expensive equipment or plenty of spare time and notebooks. But today鈥檚 self-trackers have it easy. Now there are weighing scales that produce graphs of your weight, watches that count calories, motion-sensing stickers that know how often you brush your teeth, and gadgets that tell women they are ovulating (see 鈥淭here鈥檚 an app for that鈥︹).

If these tools really can deliver on the promises being made for them, it won鈥檛 be long before we see an awful lot more of them. But do they actually work, how easy are they to use, and what are the downsides? To find out I kitted myself out and set off on a month-long journey of data-driven self-discovery.

Devices that measure physical activity make up the biggest slice of the personal data gadget market. Little wonder when simply wearing a pedometer can boost activity levels, with those using the devices taking an average of 27 per cent more steps per day than those who do not use them. That鈥檚 2491 extra paces (). Pedometer use is associated with lower body mass index and blood pressure. However, studies show that only people given specific targets tend to show improvements.

This has been taken on board by device designers. I used a ultra, a pedometer that set me a daily target, and gave me rewards for reaching certain milestones. This explains why I found myself pacing around in circles at home in the middle of the night: I knew I would be emailed a digital badge for reaching 15,000 steps. I had succumbed to 鈥済补尘颈蹿颈肠补迟颈辞苍鈥 鈥 the use of game mechanics for motivation to perform chores and other tasks 鈥 which many developers build into their devices to make sure people meet their targets.

Many self-quantifiers say simply keeping track of their activity makes them more efficient. As a writer prone to distraction, that idea was attractive. So I downloaded , which records the software and websites I use, decides whether they are productive and serves up the results in graphs and stats. It offers productivity-boosting tools such as temporary blocking of online distractions. RescueTime鈥檚 developers have claimed that consistent users save on average 3 hours 54 minutes per week.

鈥淢any self-trackers say simply keeping track of their activity makes them more efficient鈥

It had some obvious shortcomings, such as defining email as of neutral productivity and Twitter as highly unproductive, when I use both for work. Users with more patience than me can customise it by assigning personal productivity ratings to activities and manually defining time away from their screens. Still, RescueTime did show that I am consistently more productive later in the day. It provides a score out of 100: my average was 72 in the afternoon compared to 60 before lunch.

One of the more innovative self-quantifying gadgets is the , a forehead sensor that tracks your sleep. The sensor picks up electrical signals from the brain, as well as muscle contractions and eye movements, to measure deep, light, REM and total sleep. This data is sent via bluetooth to users鈥 smartphones and presented in daily graphs. That鈥檚 useful to know considering that recent studies have shown that insufficient sleep is associated with increased risk of higher body fat levels, type 2 diabetes, heart attacks and impaired immune system functioning.

My average night鈥檚 sleep lasted 6 hours 57 minutes, of which 2 hours 52 minutes was REM sleep, and 59 minutes was deep sleep. As the test went on I noticed I was going to bed earlier. By the end of the month, I was sleeping around an hour longer than I was when the test started.

Perhaps that鈥檚 because my experiment was influencing my behaviour. Such an effect has been known to psychologists since at least the 1920s, when the owners of the Hawthorne Works near Chicago carried out experiments to see how light levels affected productivity. They were surprised to find that no matter how they changed the lighting conditions, workers always became more productive than usual. It turned out the workers were working harder because they knew they were being studied 鈥 a phenomenon called the .

Self-quantification can also help fine-tune bad habits to minimise their harmful effects. While I knew that drinking too much alcohol , I did not know how much was too much. But the Zeo provided concrete answers. Correlating my Zeo鈥檚 daily sleep graphs with my alcohol consumption showed that my best night鈥檚 sleep of all occurred on a night when I had two glasses of wine; when I consumed more, both sleep quality and quantity were hit.

Early learning

Combining data from different aspects of our lives can be powerful. That鈥檚 what Larry Smarr did. Director of the California Institute for Telecommunications and Information Technology in La Jolla, Smarr is an early adopter and unofficial ambassador of the quantified life. He not only uses Zeo and Fitbit but routinely has blood and stool samples analysed for biochemical disease markers.

In 2008, this revealed his levels of the inflammatory marker C-reactive protein (CRP) were more than 10 times higher than normal. His doctor told him not to worry but to return if he had any symptoms. A few months later he felt intense pains in his abdomen. This time the doctor diagnosed a colon wall infection. Smarr knew that elevated CRP could indicate a build up of plaques and an increased risk of heart attack, so he paid for ultrasound scans, which showed his carotid artery was thickening. Could his heart be in trouble? Then, a stool sample analysis showed he had more than 100 times the normal level of lactoferrin, another inflammation marker. Smarr took his data to a gastroenterologist who concluded that Smarr may have a mild form of Crohn鈥檚 disease.

鈥淒iseases in modern medicine are determined by symptoms, as they have been for hundreds of years,鈥 he says. 鈥淨uantified health is in the process of completely changing that.鈥 Smarr thinks self-tracking will lead to a future in which diseases will be diagnosed before symptoms set in.

It could also usher in a new era of personalised medicine. Think of all the norms and guidelines by which you live your life 鈥 how many actually apply to you? For example, we are advised to eat two 140-gram portions of oily fish per week no matter what we weigh. Regardless of when we perform at our best, most of us work from nine till five. Women in the US are every three years from the age of 47, largely irrespective of their specific genetic risks.

These conventions are applied despite the decades scientists have spent defining the multitude of ways we vary as individuals, from our vulnerability to illness and dietary needs to our body clocks and alcohol tolerance. The 鈥渢yranny of the average鈥 has held sway for so long largely because of our inability to keep track of our data. Few individuals have had the time to keep records of things like sleep patterns, blood glucose, activity and diet.

Self-tracking could change all that. In his recent book The Creative Destruction of Medicine, cardiologist Eric Topol describes how treating people in the same way just because they have similar symptoms can be frustrating, wasteful and potentially harmful. For example, the leading anticoagulant Plavix, which is often given to patients who have had stents inserted to prop open diseased coronary arteries, is less effective in 30 per cent of people with genetic variants that stops them metabolising the drug, potentially putting some at an increased risk of blood clots. Mass cancer screenings may extend some lives but it can also lead to preventative surgery that could be unnecessary in some cases, such as mastectomies. Now, with huge amounts of medical information and personal data at our fingertips, medicine is ripe for radical transformation, says Topol.

鈥淲ith huge amounts of medical information and personal data at our fingertips, medicine is ripe for radical transformation鈥

Granted, not everyone will rush to analyse their stools like Smarr did. But thousands of people who have migraines, allergies and diabetes, for example, are tracking their diet, medication, sleep and health metrics 鈥 such as blood glucose levels and heart rate 鈥 in a bid to identify correlations.

Topol is not alone in seeing personal health tracking as a way of redefining the doctor-patient relationship. 鈥淚nteractive tools and devices will take some of the burden and delay out of the existing system,鈥 says Matt Jameson Evans, an orthopaedic surgeon who co-founded HealthUnlocked, a UK company specialising in online health tools.

To cash-strapped public health providers, novel technologies and greater patient involvement are attractive. The first results from the UK Department of Health鈥檚 , the largest evaluation of remote healthcare tools conducted to date, were published in June. Every day, those in the trial 鈥 1365 people with heart failure, diabetes and chronic obstructive pulmonary disease (COPD) 鈥 measured variables such as weight, blood glucose, pulse rate and blood oxygen saturation, and sent the results to their doctors. In the year following the trial, those that did the remote measuring were 6 per cent less likely to be admitted to hospital compared to the trial鈥檚 control group. More interestingly, they were also 20 per cent less likely to have to be admitted as an emergency ().

Self-tracking could even generate new medical knowledge. On websites like PatientsLikeMe and CureTogether, tens of thousands of people already share data on symptoms and treatments for hundreds of illnesses. Last year, CureTogether analysed data submitted by members who had been using the drug Imitrex to treat migraine. The analysis revealed that those who suffered from vertigo or dizziness alongside their migraines were 3.1 times more likely to feel worse after taking the drug than those who did not suffer these additional symptoms.

Not everyone thinks self-tracking is ready for prime time. A key problem is the failure of devices to talk to each other. Although I wanted to see how my physical activity affected my sleep, I could see no easy way to combine my Fitbit and Zeo data. Until developers make it easier for people to manage their data, self-quantifying will be held back from mainstream use, says Adriana Lukas, founder of the Quantified Self London group.

And in common with other technologies, the gadgets will only sell widely if they are easy to use. I tried a system called to quantify my skills during the weekly football matches I play. It was supposed to tell me how far and fast I ran, and the speed and spin I put on the ball. Unfortunately, it was baffling to use, buggy, and not terribly relevant to the skills needed in defence, where I play.

Some fear that self-tracking could soon become expensive or inconvenient to avoid. Already, some car insurers offer discounts if drivers install driving monitors, and health insurers are watching these developments closely. That raises privacy issues. 鈥淥nce the data exists, it鈥檚 going to be very hard to keep control over it if you have given it to a third party,鈥 says Lukas.

Despite these issues, the Quantified Self movement has gained momentum. Its membership doubled in size in the first six months of this year to more than 11,000 members in 69 cities across six continents. As the technologies improve, the personal and commercial benefits they offer could make it an unstoppable trend. With Apple being one of several big players working on self-tracking devices, it is unlikely to be long before the ability to free us from the tyrannies of the average will outweigh potential costs.

My month of self-quantification taught me several things. Paying more attention to things in your life by tracking them can lead to behavioural changes. Getting new data and well-presented graphs is only interesting in itself for a short time. The time and hassle involved in charging devices and recording data is only worth it if you鈥檙e really motivated. And targets only work for so long before the novelty wears off, even when you鈥檙e the proud owner of a badge for walking 15,000 steps.

Quantify thyself: Tracking your life from food to mood