It
is an astonishing fact that the human body is basically two thirds water. Without
it most people are dead in four days. In normal circumstances in twenty four
hours we lose 1.5 liters of water in urine, 750ml through the skin, 400ml in
the breath and 150 ml in the faeces. That’s a total of 2.8 liters a day. A
simple equation would suggest that this is what you need to drink.
It isn’t quite simple, however, firstly,
the body makes water by metabolizing food, normally provides around 1 liter a
day. This totals 1.3 liters, leaving the average person 1.5 liters short or an
average day. That’s the equivalent of six glasses of water.
Drinking a total of 1.5 liters of water a
day is really a minimal since if it is hot or you exercise you will need more
because you will sweat more. Also, drinking more is generally helpful for the
kidneys. This is because many toxins, both generated by the body and the ones
that are consumed, are eliminated via the kidneys. By diluting the
concentration of these toxins in the blood you give your kidneys an easier
time, up to a point.
In fact, it’s essential to ensure that
enough fluid is available for the excretion of soluble minerals in the blood
and nitrogenous waste material, especially from protein metabolism.
The maximum intake from oral liquids should
be that which the kidneys can reasonably excrete in 24 hours, and in adults
this is around 2 liters per day.
Contrary to popular opinion, drinking more
water doesn’t leach minerals from the body according to mineral expert Dr Neil
Ward of the University of Surry, who has never found any evidence of this or
reason it would happen.
Drinking more than you need, which is
around 1.5 to 2 liters a day in normal circumstances, isn’t better for you, and
may be worse. This is because too much water taxes the kidneys and can lead to
over- hydration. Taken to the extreme this can kill you. A man died recently
after drinking 10 liters in a few hours, while almost every year somebody dies
from drinking too much water while on Ecstasy, for fear of drinking too little.
This drug, and others, disturbs the normal thirst reflex. Far more people die
as a consequence of drinking too little.
Water has many roles throughout the body
other than flushing the kidneys, including dissolving minerals, and acting as a
delivery system, a lubricant and a temperature regulator.
Even very mild dehydration can lead to
constipation, headaches, lethargy and mental confusion, while increasing the
risk of urinary tract infections and kidney stones. When just 1% of body fluids
are lost, body temperature goes up and concentration becomes more difficult.
The thirst mechanism kicks in when we’ve
lost between 1 and 2% of body water, however, the thirst reflex is often
mistaken for hunger. If we ignore it or mistake it for hunger, dehydration can
continue to around 3%, where it seriously affects both mental and physical
performance. Sports nutritionists have found that a 3% loss of body water
results in an 8% loss in muscle strength.
Water consumption advice almost always specifically
discounts caffeinated beverages, but this is now being questioned, and may need
revising. Caffeine does cause a loss of water, but only a fraction of water you’re
adding by drinking the beverage. In people who don’t regularly consume
caffeine, for example researchers say that a cup of coffee actually adds about
two thirds the amount of hydrating fluid that’s in a cup of water. Regular
coffee and tea drinkers become accustomed to caffeine and loose little, if any,
fluid. The only common drinks that produce a net loss of fluids are those
containing alcohol.
The best way to hydrate the body though, is
water or herbal teas.
David
Foley
MRCHM,
MNIMH
Medical
Herbalist
