I've smoked for nearly 40 years. Since the lung damage must be irreversible, is there much point in stopping now?

There's plenty of point. Some years ago, Danish researchers found that when people with chronic obstructive lung disease (it used to be called chronic bronchitis) stopped smoking, they had 40% fewer illnesses than those who continued to smoke. Those who cut down, rather than cut out completely, showed no improvement in their health. The lesson is to stop, not to be half-hearted about it.

I read a leaflet in our local surgery stating broadly that coffee is good for us, and that it's safe for pregnant women to drink three or four cups a day. What do you think of that?

I know about the leaflet - it's called Coffee And Your Health and is produced by the British Coffee Association. The association says that it follows the Food Standards Agency (FSA) guidelines that linked high caffeine intake during pregnancy to increased numbers of miscarriages and of babies born with low birth weight. High intake per day is defined as four mugs of instant coffee, three single espressos or six cups of tea, so the leaflet suggests that drinking up to that level is safe. The FSA is studying the effects of caffeine in pregnancy in more than 2,000 women. Let's see what that concludes, hopefully this autumn. In the meantime, I'm advising my patients to go easy on the coffee during pregnancy. There is no evidence that it is harmful in lower 'doses', but we don't know for sure.

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