The Numbers That Try to Tell Us How to Eat and Move
At 44, I’m old enough to remember a time before numbers were everywhere. I remember when no one knew how many calories there were in anything they ate, or what their resting heart rate was, or how many paces they’d done today, or how long they spent in REM sleep last night. The everyday human activities—eating, walking, sleeping, shopping—have remained, but they’ve been superimposed by a layer of arithmetic. It’s happened gradually, this insertion into our lives of numbers that we’re meant to live by: kilocalories, grams of macros, heart-rate zones, heart-rate variability, steps, elevation gains, litres, hours of direct sun exposure… The progressive numerical infiltration has taken two forms: normalizing tracking and supplementing the tracking with targets and limits. Not very long ago, mainstream health advice amounted to innocuous platitudes such as, “don’t eat too much”, “get plenty of fresh air”, “stay active”. Now, what counts as enough or too much has been converted into numbers: 10,000 steps a day, 150 minutes of moderate exercise a week, 5 portions of fruit and veg a …








