But the problem with the festive season is not the parties themselves, it's keeping up in between them. Hangover days follow a familiar ritual - as I remembered the morning after, when I shuffled to Prêt à Manger for breakfast and from there to my desk, weighed down with carbs and coffee. I took only shallow breaths and made no sudden movement. To stay hydrated, I made pilgrimages to the water fountain 10 times an hour and was grateful for the ad hoc pharmacy on my desk: vitamins, painkillers and a huge jar of multivitamins.