How can I prevent the dehydrating effects of alcohol?

Q: How much water should one drink with a glass of wine to prevent alcohol-induced dehydration?

A: There is a lot of misunderstanding around alcohol, dehydration and hangovers. While alcohol is a diuretic (promoting water loss through the kidneys), this doesn’t mean that all alcoholic drinks inevitably cause dehydration. It all depends on the strength and volume.

Beer and lager drinkers take in far more fluid than is lost through the diuretic action of the alcohol, resulting in a net gain of 300-400ml for every pint drunk according to a recent review by the British Nutrition Foundation. A single shot of spirits results in a 75ml net loss, so as long as you drink each shot with a mixer you are unlikely to end up dehydrated.

Wine also causes dehydration with the average person producing 350ml of urine for every large (250ml) glass drunk, resulting in a net loss of 100ml per glass – or a third of a litre for every bottle drunk. Make that up with water and you should maintain the status quo.

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