If you have sleep problems, or are the sort of person who might be worried your sleep isn’t as good as it should be, tracking how much you are getting can become an unhealthy fixation. “If you have a device that is telling you, rightly or wrongly, that your sleep is really bad then that is going to increase your anxiety and may well drive more... See more

In the last 10 years there have been mobile apps and smartwatches and bed straps that promise to capture how well we are (or aren’t) sleeping.

Another problem with trackers is that sleep requirements are unique to each person. The “ideal” eight hours sleep a night is an average – some people will need more, some less; being told you are falling short can cause anxiety. “The population level data would suggest most adults need somewhere between seven and nine hours sleep a night, on... See more