Self Tracking for the Rest of Us

In his new book, “Personal Science,” quantified-self expert Gary Wolf shares how to hone your observational skills to optimize your health.

Just as personal computers brought the power of the pre-1980s expensive mainframes to the masses, the emerging popularity of personal science is making the techniques of professional science available to everyone. In his new self-published book, Personal Science: Learning to Observe, writer and researcher Gary Wolf summarizes the lessons learned from people who’ve been practicing these ideas for more than a decade—sometimes called quantified selfers, sometimes biohackers, sometimes citizen scientists, and sometimes simply, self-trackers.

I first encountered the term “personal science” through my friendship with the late University of California, Berkeley psychology professor Seth Roberts, who for decades kept rigorous daily diaries of his sleep, diet, and many other aspects of personal health. His 2004 academic paper, “Self-Experimentation” offers ten examples of intriguing takeaways he learned about himself. Mining his personal data, he found statistically significant effects on his mood, sleep, and weight, through unconventional yet simple interventions like seeing faces (real or on-screen) in the morning or drinking unflavored fructose water.

Nobody is more familiar with this history than Wolf, who coined the term quantified self in 2008 with former Wired editor Kevin Kelly and others who noticed that technology was making it easier for individuals to record and study their lives quantitatively. Soon a series of regular quantified-self meetups began to spring up, first in the Bay Area, but eventually all over the world. Several worldwide conferences attracted thousands of like-minded individuals. Dozens of successful products, including Fitbit and Oura, were inspired by these events and eagerly sought by the participants.

His new book is a systematic summary of the key ideas and lessons of the quantified-self movement. Written with the help of other long-time quantified-self influencers, it’s liberally sprinkled with anecdotes from people who’ve applied the principles of science to their daily lives, sometimes in order to counter devastating illness.

The book’s co-author Sara Riggare, for instance, used a simple iPhone tapping game to track her Parkinson’s symptoms. Upon seeing patterns in how her symptoms varied throughout the day, she was able to adjust her medication schedule to optimize its effectiveness. wrote about the academic challenge to self-experimentation she encountered while self tracking for her PhD. We also meet Whitney Erin Boesel, who was concerned about her high blood cholesterol after pregnancy and used daily tracking to learn that her cholesterol levels varied significantly throughout her menstrual cycle. The wealth of data gave her confidence to spot meaningfully high levels against a background of variation.

Most of all, the book is a guide for the rest of us: How anyone can fine-tune their observation skills and hone record-keeping habits similar to the way professional scientists do—the learning to observe of the book’s subtitle.

How to find your quantified self

Wolf and his co-authors offer concrete suggestions for how to focus on what’s important and advocate that you should start simply. If you’re trying to solve a health-related problem, for instance, ask yourself: What exactly is my concern? They stress moving beyond the general question of disease identity and into the more personal one of how it affects you specifically. Where is the pain? How severe is it? How frequently do I feel it? And what helps?

Wolf and his collaborators offer simple best-practice advice throughout the book: Keep a time series, make a log of your symptoms (but don’t get carried away), and above all keep it personal. An article or YouTube video from somebody else might be a useful starting point, but never assume that what works for others will work for you. Even well-done clinical trials report only what works for most people, not everyone. There are almost always outliers, and maybe you’re one. Greg Pomerantz, for example, tried a low-carb diet for three years on general advice from popular articles and videos that claim the benefits of glucose control. But when, curious about the effects on himself, he switched to a high-carb diet, he learned that his body continued to maintain healthy blood sugar levels despite the warnings he’d seen from others. Everyone is different and personal science is about learning about you.

Observation skills can be honed, and the authors suggest a dozen specific areas to improve. Use surrogate end points (or “proxies”), for example. When confronted by a task that’s too burdensome or impossible to track on its own, look for similar measures that are “close enough,” such as the number of aspirin you take in a week instead of the number of headaches.

Everyone—including professional scientists—benefits when we share our data with others.

And don’t go overboard trying to squeeze the last decimal point out of your observations. For example, rather than rate your daily mood on a scale from one to ten, use “the rule of three”—sad, neutral, happy. Better yet, be like Dutch designer Ellis Bartholomeus, who simply wrote a happy or sad face in her daily notebook. And be patient: A single daily qualitative self-assessment written in a notebook each day accumulates into a large quantitative data set over time.

Once you’ve collected your observations, the authors suggest techniques for better reasoning skills. If you can collect similar data from two separate sources, for example, overlay them against each other to spot differences. Gary Wolf himself did this when trying to find the source of his heart arrhythmia. Although the two devices mostly agreed, the differences at nighttime were significant enough to suggest behavior modifications that helped him manage his symptoms.

The personal scientist in action

Questioning, observing, and reasoning are essential skills for a personal scientist, but the book’s final section, about discovering, describes how everyone—including professional scientists—benefits when we share our data with others. It’s noteworthy that the authors are champions of the “open science” movement, with its ethic of transparency, free availability, and ongoing disclosure of methods and data. Each of the book’s examples plus hundreds more are documented in free videos on the Quantified Self Show & Tell forums.

Interestingly, the book never mentions the word “privacy,” nor does it include lawyerly disclaimers about the need to “talk to your doctor first.” Perhaps later editions will include practical tips to inadvertently avoid disclosing private information, but I suspect the authors take it for granted that a good personal scientist, always curious and open-minded, wants to be open and sharing. 

Although the book documents numerous examples of people solving their own problems, it’s the techniques that are emphasized, not the conclusions. This emphasis on methods, without conclusions on health advice, makes this a valuable addition to the sparse bookshelf of the quantified-self movement. It’s certainly not the first book to appear on the subject. contributor David Ewing Duncan’s 2009 book The Experimental Man is a personal attempt to “humanize science by having a real person with a family and children intimately participate in leading-edge technologies.” Joseph Reagle’s Hacking Life summarizes many of the field’s ideas and colorful characters. The web and social media are full of examples of everyday people applying the principles of science to ask questions and solve problems. Besides Quantified Self, hundreds of sites dispense personal examples, with step-by-step instructions. Some of my favorites are, Quantified Bob, Open Humans, and The Quantified Body.

Nevertheless, this book is an excellent introduction filled with useful ideas and instructions. Fundamentally, personal science is about doing. If you have a Fitbit or Apple Watch, Oura Ring or Whoop, you’re already accumulating interesting information about yourself that can help you act like a personal scientist. 

Author’s note: I am proud to be one of the dozens whose work in this field is cited in the book, but I have no formal relationship with the authors.

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