Our social order is made up of widely accepted myths and legends. A glass of wine a day is good for your health, a dog year equals seven human years, you have five seconds to put food on the ground in your mouth. And another one that we have followed to the letter for years: you have to walk 10,000 steps a day to enjoy a long and healthy life. You know it, your mother knows it, Google knows it and a lot of scientists who have studied the matter thoroughly know it.
Because they know, right?
Dismantling myths. Well, it turns out not. As we will see a few paragraphs later, the 10,000 steps long ago fell into the category of unverified “myth”, but today science has seen fit to confirm it. A study published in JAMA has discovered that the optimal number of daily steps is around 8,000 and that from there the effects on our body are discrete. Very discreet. Yes: you have been taking 2,000 more steps for years that no one is going to give you back.
The procedure. The authors selected 2,110 participants between the ages of 38 and 50, gave them an accelerometer, and measured their number of daily steps for ten years. Their activity would be classified into three categories: “low” for those who walk less than 7,000 steps; “average” for those who walked between 7,000 and 9,000; and “high” for those who exceed 10,000. A decade later they collected the data and found that those who took at least 7,000 steps a day had between 50% and 70% less risk of premature death from health reasons.
Blame Japan. Two years ago, an epidemiologist at Harvard University set out to find the origin of the blissful “10,000 steps.” Their study shed light on the imperfect information that humans often handle in our day-to-day lives. The figure came from an advertising campaign launched in 1965 by Yamasa Clock and Instrumens, a Japanese manufacturer of pedometers. They christened their product “10,000 step meter” … Just because the Japanese alphabet character for the number 10,000 (万) looks like a man walking.
It lasted. As we have seen, the ad was successful because one of its promoters, Yoshiro Hatano, an academic at Kyushu Health and Wellness University, took advantage of the hangover from the 1964 Olympics to promote a more active and healthy lifestyle. At that time, the average Japanese walked about 4,000 steps a day. Hatano thought promoting a much rounder and more striking figure, 10,000, would help them get going (and selling more pedometers).
Less steps. Other works had already illustrated in the past how 10,000 steps were too many, and how keeping our daily activity around 7,500 (about 4.5 kilometers) was more than enough and beneficial. Nobody doubts the positive impact of moving daily. Walking as a healthy activity is not a legend and it has lasting and very healthy effects. Yes, the magic number is, knowing how we know that some excesses of activity are compensated by eating more.
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