See what drinking water can do to your skin: Took 10 years of this woman's face

You might think I'd have little in common with a camel, but we do share one useful skill: both of us can go for a very long time without water.

Usually I start my day with a cup of tea, then I might have a glass of water with my lunch and one with dinner - that's about a litre of liquid in 24 hours. It feels like plenty, but apparently it's not nearly enough.

After years of suffering headaches and poor digestion I spoke to a neurologist about my regular headaches and a nutritionist about my poor digestion, and both told me I should be drinking up to three litres of liquid a day for my body to function at its best.

Then, when I read a recent survey suggesting that at least one in five women in the UK consumes less than the recommended daily intake of water, I decided to conduct an experiment. What would happen if I drank the recommended amount every day for a month?

The photograph of me taken the day I started this trial demonstrates perfectly - and rather frighteningly - what a lack of hydration does to a face.

I am 42, but have to admit I look more like 52 in this picture, which is shocking. There are dark shadows under and around my eyes, which make me look exhausted, a profusion of wrinkles and strange reddish blotches, and my skin lacks any lustre. It looks dead.

Even my lips look shrivelled. This is all classic evidence of poor hydration, apparently. Every system and function in our body depends on water.

It flushes toxins from the vital organs, carries nutrients to cells, provides a moist environment for ear, nose and throat tissues, and eliminates waste.

Not drinking enough means all these functions become impaired. So I decided to see how I would look and feel if I drank three litres of water every day for 28 days. The results were astonishing . . .