Once heard a doctor say "as long as it's not interfering with your normal day - ie, you're not doing it at work or in public etc, it's perfectly fine".
Of course, I've done it in public and at work before, and I'm perfectly healthy....

My eyesight's gettin worse though, I reckon...
CasperTG

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You know, Blackadder, for me socks are like sex. Tons of it about and I never seem to get any.

My Photos:
https://imgur.com/a/80hiRdm