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.
After four weeks: Sarah looks like a different woman
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.
My daughters, Alice, eight, and Betty, four, tell me I look 'about 100 years old' in this photograph and I have to agree.
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 . . .
Dehydration: One in five women consumes less than the recommended daily intake of water
Weight: 8st 7lb
Three litres of water is just over five pints, which sounds like an awful lot. I visit my local GP in Hebden Bridge, Yorkshire, to be sure there can be no adverse health implications to upping my water intake so dramatically.
He is very encouraging. 'I suggest you have a big jug of water in the morning, then another in the afternoon and another in the evening,' he says. 'Your kidneys, which filter waste products from the blood before turning it to urine, will quickly feel the benefit, as they will be getting a good flush through.'
I usually have a wee three times a day: when I get up, before I go to bed and at some point in the afternoon. By the end of my first day of drinking more water, I have had six and my usually sluggish bowels are much more lively.
I exfoliate my face every day to try to get rid of dry patches before I apply moisturiser, but suddenly I seem to be breaking out in spots. Maybe it's all the toxins coming out of my skin. A few days into the experiment I'm still urinating five or six times a day but it's clear now, rather than dark yellow.
I'm enjoying lots of cups of tea. My husband says that's cheating, but I tell him the British Nutritional Foundation says 'moderate amounts of caffeine do not cause dehydration, so they do count towards your fluid intake'.
I meet friends for a drink one night, remembering that alcohol is a diuretic (a substance which promotes the production of urine), acting on the kidneys. For every one alcoholic drink, your body can eliminate up to four times as much liquid.
I assume a white wine spritzer is a good option because the alcohol is diluted with soda water, and I sip water between alcoholic drinks throughout the evening.
Hangover headaches result from dehydration: the body's organs try to make up for a lack of water by stealing it from the brain, as a result of which it actually shrinks.
Headaches result from the pulling on the membranes that connect your brain to your skull. Ouch. Luckily, I escape all this and wake up hangover-free.
For years I've been doing ten minutes of yoga every morning straight after I get up, but I've been feeling stiffer over the past six months. Yet since I started drinking more water my flexibility has improved. Gemma Critchley, from the British Dietetic Association, confirms that water helps lubricate the joints.
Week Two: The blotches on my face are diminishing and the shadows around my eyes less pronounced
Weight: 8st 6lb (lost a pound)
My complexion is improving and my skin tone is more even. I still have wrinkles under my eyes, but they look less crepey and shadowy than before.
The blotches on my face are diminishing, and the shadows around my eyes are less pronounced.
I feel pleased when my sister-in-law tells me my skin looks clearer than it did a week ago. I have a busy week with lots of time away from home, so I stock up on half-litre bottles of mineral water I can carry around in my bag. A week's worth costs just over £8. If I spread my water intake over the day, that's half a litre when I wake up, another with breakfast, one with lunch, one in the afternoon, one with my evening meal then another before bed. It sounds like a lot, but I'm finding it manageable.
Today, I've noticed my breath smells less 'breathy', maybe because I've ditched tea - I decided water was better for me. I'm certainly not missing the sweet, milky taste it left in my mouth.
Gemma Critchley says: 'Water is obviously the best choice since it has no calories and will hydrate you efficiently.' I say I might try juice instead of water sometimes, just for the taste and variety, but she warns me not to.
'If you drink a large glass of juice, you could be consuming more energy than you need,' she says, which would mean weight gain.
I haven't had a headache for over a week now, which is unusual for me, and I'm delighted that my bowels are working so much better. Result!
I went shopping this afternoon in Leeds, but having to find a lavatory three times in five hours was irritating - they always seem to be in the most hidden corner of every shop.
I'd expected my stomach to feel bloated with all the extra water but it's actually flatter than usual. And my husband says the cellulite on my bottom and thighs has vanished.
Surely this is too good to be true?
Week Three: My skin looks plumper and more nourished
Weight: 8st 6lb
Waist: 27.5in (lost half an inch)
The dark rings and wrinkles under my eyes have virtually disappeared, and my skin looks plumper and more nourished. My friend, who is a beauty therapist, says this is because the water is helping my skin cells regenerate more efficiently.
I've noticed I've stopped rubbing my eyes when I wake up in the morning. They used to be dry and full of sleep, but not now. All this extra water must be keeping them moist.
I'm feeling guilty about all the plastic bottles I've been using so I'm back on Yorkshire tap water, which I carry around in a re-usable water bottle.
I have to take a long train journey and I realise afterwards how productive I felt and how easy I found it to concentrate, rather than having my customary snooze.
Dr Emma Derbyshire, senior lecturer in nutritional physiology at Manchester Metropolitan University and adviser to the Natural Hydration Council, says: 'Our brain is 73 per cent water, so poor hydration can affect how it functions. Dehydration can reduce our ability to concentrate as well as our cognitive performance.'
The downside was having to use train toilets. Dreadful.
I'm eating less because drinking water with meals makes me feel fuller quicker. I used to snack, but I was reaching for food when I was actually thirsty. Studies show 37 per cent of people mistake thirst for hunger.
When I put on eye make-up, my eyes seem less wrinkled. When I rubbed an eye-shadow applicator over my eyelid, it used to drag the skin with it, too, but now my skin seems to have more elasticity.
Week Four: I am going to keep on drinking three litres of water every day
Weight: 8st 5lb (lost another 1lb)
Waist: 27in (another half an inch)
I genuinely can't believe the difference in my face. I look like a different woman. The dark shadows around my eyes have all but disappeared and the blotches have gone. My skin is almost as dewy as it was when I was a child. The transformation is nothing short of remarkable.
I'm feeling leaner and fitter, too, which is amazing, since the only thing I've changed is the amount of water I drink. My best friend says she's worried about how much water I'm consuming - she's heard rumours about Nigella Lawson being an 'aquaholic' who drinks three litres before bed.
But I am following safe guidelines under the supervision of my GP, so I am able to reassure her.
I even enjoy another boozy night out but drink lots of water along the way and wake up feeling fresh as a daisy. Whatever happens, I am going to keep on drinking three litres of water a day - and would advise every woman to do the same (after checking with her doctor, of course).
I feel fitter, leaner and healthier, and my husband and friends tell me I look ten years younger. Who in their right mind would not want to try something which gets such incredible results?
That's interesting, SohiniBen, but I hope you didn't share it with all our members - just friends?
I think this is good for every one to know...But I have shared it with my friends here....
Thank you Sohini,
You eat less, when you drink more and certainly water flushes toxins and your skin and body will love you for it!.