Is alcoholism inherited?

Partly. More alcoholics than expected by chance possess a variant of the 'alcohol dehydrogenase' gene that we all use to break down and get rid of alcohol from our bodies. It lets them drink more than is healthy before they feel the ill effects. For some, that is the first step on the road to alcoholism. Anyone with any mix of genes can become alcoholic, however, suggesting that social circumstances matter more than genetics alone. On the other hand, one gene actively prevents you from becoming an alcoholic. It leads to the production of a substance called 'aldehyde dehydrogenase', which makes you feel sick and ill after drinking only a small amount. Draw your own conclusion on who are the lucky ones.

Is there any evidence that the current flu vaccine really works?

Dozens of papers and surveys published since the 1970s show that repeated annual vaccination of 'at risk' people with updated flu vaccines reduces their chance of catching it by about 70%. It also reduces the severity of the illness in people who do catch flu after the vaccination. So it is as successful a vaccine as most. The problem will come when a new virus, with none of the surface antigens (used to make the vaccine) of the previous ones, appears. The last time that happened was in 1968, when there were hundreds of thousands of cases, and thousands died. In the meantime, if you are on the risk list, it's definitely better to protect yourself than not to do so.

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