I’ve walked around 7,300km since I bought my most recent phone. I know that because, like many phones these days, it came with an app that tracks my steps. But although I've had some very long days (my record effort was 33,661 steps, recorded in the Italian Dolomites last spring), I've never managed to consistently hit the well-known target of 10,000 steps a day.

Luckily for me, that may not matter much. This week’s column is about walking as exercise, and how much of it you should do. As my colleagues point out, the famous 10,000-step target is not exactly a marvel of scientific rigour. It comes from an advertising campaign run in Japan in the 1960s.

The column contains plenty of juicy detail. But the results from various large-scale trials suggests that even relatively modest step counts are associated with big health benefits. Going from 2,000 daily steps to 4,000 resulted in a 36% drop in mortality risk over the years tracked. Going from 7,000 to the full 10,000 is associated with just a 2% further reduction in mortality risk.

You can also trade off numbers for intensity, at least to some extent. Fewer steps walked faster seems to be a reasonable alternative to a longer bout of ambling along slowly. So don’t worry if, like me, you can’t quite make it to five figures a day. 

How many steps do you take each day? Let us know via our poll. And if you have any tips for increasing your count—or your cadence—you can email us at wellinformed@economist.com. We might feature you in next week’s newsletter.

Last week we asked what your mouth-care routine looked like (and whether it included a tongue-scraper). Well over a third of readers (39%) said they used a toothbrush and floss, while 17% said they added mouthwash to the mix. A modest 12% said their routine consisted of all that—plus a tongue-scraper. Concerningly, 0.25% of respondents voted for “nothing”. 

We also asked if you had any tips for keeping your teeth, tongue and gums healthy. Many of you, including Hélène and Jeremy, wrote to recommend using oral probiotics as part of a dental regime. In Karachi, Saeed says the secret to his oral health is simple: “vigorously” brushing his teeth for a minimum of three minutes every day. Writing from Surrey, Rosemary, aged 96, says she still has all her “own teeth”. She uses an electric toothbrush for two minutes, twice a day. She also swears by a water flosser and uses a tongue-scraper at night. See you next week.  

“Walking is man’s best medicine,” said Hippocrates, an ancient Greek physician. Or so the story goes. Whether the phrase originated with him is disputed. But it does contain a kernel of truth. Walking is a form of exercise that is free, requires no equipment and is easy for most people to incorporate into their days. But how many steps should one walk—and at what speed—to unlock its benefits?