Many of my friends who are now in their 60s and 70s are more affected by moderate amounts of alcohol than when they were younger, so much so their behaviour can distress those around them. Is there a case for discouraging drinking above a certain age?

It's not age that reduces our tolerance to alcohol, but whether our previous consumption has damaged the capacity of our liver to process it, or of our brain to cope with its effects. I wouldn't advise older people who enjoy alcohol without embarrassing others to stop or even reduce it. But if it is obviously affecting their behaviour, that's an indication to do liver and brain function tests.

Are naps in the afternoon good or bad for toddlers? Do they sleep as well at night if they nap during the day?

Probably not. In Japan, where pre-school nurseries force children to take naps of over an hour each day, they were moodier in the mornings than those who slept only when they needed to. Their morning moodiness lasted for years after they no longer were forced to nap. American children taking long daytime naps didn't get to sleep as well at night, and protested more when woken, than those who didn't nap. Children at a kindergarten who took long naps in the daytime were less able to solve puzzles than those who didn't. So it seems that you can let children sleep for, say, 10 minutes in the day when they feel tired, but don't organise set times each day as a routine.

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