Flabby, vaguely disorientated and, more than three years on, still struggling with stroke recovery, I am on a radical diet. No booze, no caffeine of any kind, no lots of other things — sausages, bacon, roast meat, you name it. Not a lot of fun, but the revelation has been coffee: for well over 40 years I have believed that I can only function in the morning after pints of coal-black, extremely strong caffeine. And now, aged 57, I find that it was total horlicks all along — I feel perkier, less tired and less stressed (after a hard few days) without the stuff. This makes me a real oddity in a country in which coffee has become a massive popular cult. I wander around Baristastan, passing ’Bucks, Costas and Neros, feeling a bit like a Wahhabi in Soho at chucking-out time.