OH! Magazine - Australian Version June 2017 | Page 10

( Nutrition )
WATER AND
HYDRATION
Dr Joanna explores the importance of hydration.
re you drinking enough water? Or
are you drinking too much? Our
thirst mechanism is not our most finely
tuned body mechanism and it’s easy to
get hydration wrong. Even mild
dehydration affects your cognitive ability,
exercise performance, blood pressure
and heart rate increase, and in turn
kidney health can be affected. For those
with pre-existing heart conditions this
can be especially dangerous, but for all of
us dehydration has very real effects on
the way we feel and perform in daily life.
A
Not only is exercise performance affected,
but brain performance and your ability to
concentrate. If you frequently suffer mild
to moderate headaches it might be as
simple as you not drinking enough. Low
level chronic dehydration is common,
and part of the reason might be that we
consume more and more packaged foods,
which tend to be very dry, making it
necessary for us to drink more than we
would have to if following a diet of fresh
foods including plenty of fruit and
veggies.
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OH! MAGAZINE ( JUNE 2017 )
So how much water do you need to drink?
The ‘eight glasses a day’ rule is not a bad
one, but it’s worth realising that this is a
very rough estimate. The things that
affect how much fluid you lose also
influence how much you need to drink.
This includes how much you sweat,
whether it’s a hot day, if you’re in air
conditioning, your size (bigger people
tend to sweat more), whether you are
exercising, and how intense that exercise
is, and your own genetics – some people
are innately bigger sweaters than others.
Even how fit you are affects how much
you sweat, because the fitter you become,
the more efficient your body gets at
cooling itself, so often you’ll find you
sweat more readily.
You also need to consider how much fluid
you are getting from other sources. Water
is found in the foods that we eat and in
other drinks. The orange you ate for your
mid-morning snack provided a significant
amount of water, as did the soup you had
for lunch. Consider the water content of
other foods in your day. A salad of raw
veggies contains quite a lot of water, but
if you ate crackers with cheese for lunch
there is clearly not much fluid present in
that meal.
So what about the skim latte you had?
The biggest myth that continues to be
perpetuated is that coffee and tea
dehydrate you further. While it is true
that large quantities of caffeine have a
diuretic effect, the amount present in an
average coffee or tea is easily overridden
by the amount of liquid. In other words,
there is a net gain of fluid despite any
small diuretic effect. Unless you are
drinking several short blacks on the trot,
your tea and coffee will, indeed,
contribute to your overall fluid balance.
If this is all sounding rather complicated
and you’re thinking ‘well how do I know if
I am drinking enough?’ there is one very
simple test. When you go to the toilet,
check out the colour of your urine. If it’s
pale straw coloured then you are well
hydrated, but any darker than this and
you’re not. The darker your urine the
more concentrated it is, indicating the
more dehydrated you are. As well as