I read a news story about a girl sent to hospital after 'overdosing' on espresso. How damaging is caffeine and should I steer clear altogether?

Caffeine isn't damaging in itself if you drink an average amount of it. There is no real health hazard in drinking several cups a day. In fact, the latest research suggests that long-term coffee drinkers are less likely to develop dementia in old age than those who have drunk little or no coffee. This girl seriously overdosed herself. Her blood caffeine levels were high enough to give her a very fast heartbeat, and probably to dehydrate her, too. Caffeine and other chemicals in coffee act together as a diuretic (a drug that makes you produce more than normal amounts of urine) in overdose. But this has no relationship to drinking coffee normally. No one should stop drinking coffee just because of this one case.

Is it true that episodes of asthma strike every seven years?

Untreated, asthma does come in cycles, as does its related skin disease, eczema. We don't know what controls such cycles, but almost everyone with it will experience times when it is almost absent and other times when it is severe. However, the length of the cycle depends on the individual - for some it can be two years and others a lot longer. It's certainly not seven years for everyone. Today, with excellent inhaler treatments and advice on lifestyle, the cycles can be broken, so that most people with asthma treatments no longer have the 'downs' that used to distress previous generations so much.

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