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  • Writer's pictureGary Moller

How much water should I be drinking?

Updated: Mar 29

Boy drinking water while riding a bike in Samoa

"Gary, how much do you recommend I should drink in a day water wise?"

It completely depends on how much you are losing through factors such as the exercise intensity and duration, temperature, humidity, altitude and even the water content of what you are eating. Men usually sweat more, as do larger people as compared to people who are thin and wiry.

Hard and fast rules such as being required to drink 8 glasses a day can mislead. We are all very different, and hard rules may have us over or under-hydrating.

Did you know that:

  • A person with a magnesium deficiency may sweat excessively.

  • A sign of possible thyroid problems is poor heat and cold tolerance.

  • A heat-acclimatised person can sweat more but with more efficiency, and for longer before dehydration sets in, and is better at conserving their minerals such as sodium.

  • A heat acclimatised person is more aware of thirst sensations and will drink water sooner and more of it than the unacclimatised person.

Water follows salt

Water is found in three compartments in the body:

  • In the blood.

  • In the extracellular compartment.

  • Inside the trillions of your cells (intracellular).

The most important place for water to be is the intracellular compartment. If there is insufficient sodium and potassium and other trace minerals then water will not be able to transfer into the cells to maintain optimum intracellular hydration. Water will accumulate outside of the cells in the extracellular compartment.

Although the person lacking these minerals may still feel thirsty despite drinking more and more water, or if they ignore signals that they have drunk more than enough, they risk symptoms of what is called oedama, what I call "Soggy Body Syndrome". This is characterised by swollen ankles and fluid accumulation in the arms, legs and abdomen. At its worst, this water accumulation causes a condition called "Hyponatraemia", which can be fatal.

Hyponatraemia or water intoxication is now the most common cause of death in organised events such as mass participation marathons. Death by dehydration during such events is extremely rare.

How much salt do I need to be taking?

As I got older and cardiovascular health issues began to rear their ugly heads I progressively restricted my salt intake in line with cardiovascular health guidelines. My athletic performanmce and cardiovascular performance continued to decline despite the salt restriction and other measures such as adopting a more plant-based and low-cholesterol diet. When I realised how wrong I was to be doing these things and began to do the opposite, including salting my food generously, my energy levels and athletic perfmormance began to improve and have been doing so for the last 15 years.

The key to my getting my health inmproving with age, rather then the usual opposite, was the hair tissue mineral analysis (HTMA) which, among many things, gives us an indication of whether a person needs more or less minerals, including salt (sodium).

This person has low cellular sodium and potassium
This person has low cellular sodium and potassium

How to ensure you have adequate hydration

  • Ensure you are peeing every 3-4 hrs but not having to get up at night to pee.

  • Weigh yourself before exercise then immediately after. Any lost weight is probably water. So 1kg lost = 1 liter of water. Drink at least that much over the next few hours.

  • Do a hair tissue mineral analysis then repeat it at six months then once a year. This will help guide you as to whether you need more or less salt and other minerals.

A few handy tips

  • Limit drinking around eating food other than that sufficient to attenuate thirst. Excess water may dilute the digestive juices, thus compromising digestion.

  • Excessive water consumption may cause the excessive loss of minerals and other nutrients by way of watery bowell movements and excessive urination. This may conribute to poor health including chronic fatigue.

  • Insufficient water intake may lead to constipation, so getting water intake just right - not too much, not too little is essential for digestive health.

  • Weighing yourself before and after exercise is the most valuable way to determine your hydration needs.

  • Water follows salt: if your cells lack salt, you will not fully hydrate.

  • Listen to your body: it is said that by the time you feel thirsty it is too late, you are dehydrated. This is rubbish one-size-fits-all advice. If a person listens carefully then they will notice the thirst sensation early and drink more water, thus maintaining hydration, whereas the person with poor body awareness will not realise he or she is getting dehydrated until their body is screaming for water.

  • If you know you are going to be exercising in heat and humidity then prepare for it by going into a sauna once of twice a weeks for several weeks beforehand.

More reading:

Read this and the linked articles

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