In the many years that I've written this column, I've talked about sickness and disease, receptionists and nurses, complexity and simplicity, guile and guidelines. But I don't think I've ever quite focused on the cornerstone of so many doctors' working day. A nice hot cup of tea.

A while ago, I calculated that I had probably carried out a quarter of a million consultations in my career. I'm not organised enough to tell you the exact figure, though averaging out the workload on typical days, it feels like 250,000 is about right. Actually it feels like that was the number I saw last week, but let's leave feelings out of it.

So, if I get myself a cup of tea or coffee after every 12 to 15 consultations, and I certainly feel like I need one that often, then I've made more than 20,000 cups. And most of them went cold well before they were drained. That's an absurd amount of discarded dregs - but I still wouldn't have had it any other way.

I think it was Roger Neighbour who wrote that when surgeries are getting really stressful, and you are getting behind and feeling under pressure, then the best thing to do is slow down. It's fantastic advice, though incredibly difficult to implement when you are aware of a crowded waiting room, and colleagues equally under stress. But there's little doubt that mistakes get made when we put ourselves under ever increasing pressure, and mistakes can ruin more lives than one.

So, getting a cup of tea or coffee is a key way of taking the pressure off, of forcing myself to slow down. And failing to drink it is a symptom of the same problem. There is no way I am going to sip it while a patient is in my room, and there seems to be too little time between patients to sit back and enjoy it while it is still hot. So it goes cold, and after half an hour I tip it away, and the whole cycle starts again. I think this is what psychologists call a displacement activity.

It would probably have made a lot more sense if I had found myself some other stress management technique early in my career - deep breathing or yoga perhaps - rather than making 20,000 cups of tea or coffee never to be drunk. It would be good to be rational. It would also be a miracle. And it would probably have saved the practice a fair bit of money.

But the vital point is to remember that we matter too. Our job is extraordinarily complex - you have absolutely no way of knowing whether the next patient will have nothing wrong with him or be the most complex case you have ever seen - where getting it wrong would have profound implications for everyone concerned. And so it is essential that we keep our brains as unbefuddled as possible, and are as ready as we can be for whatever fate throws at us. And if that requires me to walk down the corridor, put the kettle on, chat to someone in the staff room for a minute, and return to my room with a cup of steaming beverage, then that's what I'll continue to do.

But it would be nice, now and again, to have a surgery full of simple cases that allow me to get through to the coffee break on time, rather than using the break to catch up. That's one of the big changes in my professional lifetime.

For years, I was able to keep to time. These days I struggle - possibly because I'm slowing down with age, but more likely because the cases that present to GPs seem to get ever more complex, and we then have to deal with both patient and doctor's agenda in ten minutes.

I doubt if I'm the only family doctor who thinks that is increasingly impossible. But it doesn't mean I won't stop for tea. Some things are just too important.