Drinking alcohol not only affects your speech and balance. It can also affect your colour vision. Not just alcohol. Various drugs (some contraceptives and analgesics, for example) make you less good at discriminating between colours. And there are a load of medical conditions that also affect your colour vision including MS and diabetes. In fact, often a deterioration in colour vision can be one of the first indications of a problem. This is why it is a good idea, from a health perspective, to have your vision checked by a qualified professional on a regular basis.

Now some research from Japan suggests that deterioration in colour vision may be a predictor of hypertension – a condition in which the arteries have persistently elevated blood pressure. The study looked at 872 men aged between 20 and 60. They found that, when other factors were taken into account, as blood pressure values rose, the odds of having impaired colour vision increased as well.

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