The health of water demystified

Water can be a confusing subject. How much should you drink a day? What is the best water to consume? What temperature should it be? These are all questions that I get asked often.


Being hydrated is optimal for your body but what does that mean in reality? Is there any evidence that eight cups a day is the optimum amount?

Actually, no there isn’t. And much like the ‘ten-thousand-steps-a-day’ mantra - which was invented by a pedometer company - it isn’t harmful to drink eight glasses of water, but there is no conclusive evidence to substantiate this is the optimum amount.

Can you overhydrate?

Yes, you can. This is one of the main reasons that runners collapse mid-marathon, as they drink too much water. When you sweat, you not only lose water in your perspiration but also chloride and sodium. If you don’t replace the electrolytes, the lack of sodium can cause heart arrhythmias, often associated with sudden death during endurance exercise.

What is better, tap water or bottled water?

After the health scare of bisphenol A (BPA), plastic bottled waters are now ‘BPA’ free and instead use bisphenol S (BPS) which is supposed to be less harmful than BPA. However, evidence is now suggesting that BPS is just as bad. So, if you drink bottled water, drink it from a glass bottle to ensure that you are not consuming harmful chemicals leaked into the water.

With tap water you are at risk of consuming antibiotics that are lurking in the water, as well as the damage that the added fluoride can have on your health - particularly for those with thyroid issues. It also depends on the filtration system that your local area uses and whether your water is hard or soft. Interestingly, the lithium in hard water may be advantageous for heart health.

So, from a health perspective, glass bottled water is best, but if that’s a cost too far, investigate the various water filter options available. A proper water filter should get rid of most of the nasties from tap water.

Is sparkling water bad for you?

Some sparkling waters are acidic, so it’s best not to consume them in large quantities. However, the pH of Italian sparkling water must be neutralised before it goes on sale. So, if you are going to drink sparkling water make sure its an Italian one – San Pellegrino is a favourite of mine!

Should you drink iced water?

As the body must use heat as energy to warm up iced water, from a metabolism perspective consuming iced water is good to help manage weight. If you suffer with a metabolism disorder such as thyroid disease, you might be best to stick with water at room temperature, as this will put less strain on the system.

So, there is more to water than you may think! Given that your body is 60% water, it is worth making sure that you are consuming the right kind, in the right way to make sure you are predominantly high-quality!

If you would like to get more advice on water consumption or learn how to ensure you are getting optimum nutrition, then a nutritional therapist may be able to help. Use our search tool to find a qualified nutritionist near you.

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

Victoria is a qualified Nutritional Therapist and member of BANT, focusing on autoimmune disease including skin disorders, heart disease and neurological issues, gut health and fatigue. Victoria has a BSc in Biochemistry & Immunology which she uses in her practice, using only evidence-based nutritional therapies to support chronic conditions.

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