Time to hydrate

All this week we’re focusing on Nutrition and Hydration Week, an awareness campaign that could be custom made for us. It’s aim is to spread the important message of maintaining health by considering our nutrition and hydration.

Today we’re looking at the most basic and yet the most vital aspect of nutrition and hydration: Water.


Why not try infusing your water with fresh fruits or herbs for extra flavour?

Aqua. H2O. Whether you take it still, sparkling, tap or bottled, infused or iced there is no escaping the importance of water to our bodies.

Our bodies are roughly two thirds water and it role is crucial. It can be incredibly difficult to know how much to drink, especially once you start to consider the impact of the exercise, weather and general state of health.

Water is not just important for the normal functioning of our bodies. It can have a crucial role in weight loss. Drinking with your meal or between meals can help to increase your sense of fullness. Those hunger pangs might not be hunger, often it’s thirst.

The human body has evolved to be a highly sophisticated filtration system. A series of chemical reactions and responses triggering further reactions and responses to maintain as steady state as possible (homeostasis).

The amount we drink is triggered by our thirst response. We drink when we’re thirsty, our body utilises the fluid it needs and any excess is eliminated by the kidneys or bowels. To counteract this loss, the thirst cycle starts again.


The actual amounts we are recommended to drink can vary depending on what study you read. In general terms, the European Food Safety Authority suggest 2L for men and 1.6L for women. Within the UK, the average bottle of water is about 500ml – so a man would need around four of these and women just over three.

However, it starts to get more complicated when you factor in the level of activity that you engage in, your physical health, your size and weight and whether it’s a hot day or not.

I often find I am encouraging my patients to drink more, and there seems to be some confusion over what we should be drinking. Water is always going to be the best option. Alcohol may feel like it quenches your thirst but it’s a diuretic meaning you’ll pass urine more frequently which may actually dehydrate you. The hangover effect and the ubiquitous headache with alcohol, in part, is due to this dehydration mechanism. One option is to alternate your alcoholic drinks with a glass of water to help counteract the dehydration.

Fruit juices and soft drinks are also options, but these can contain high amounts of sugars so should be drunk in moderation.

The vast majority of tea and coffee, unless you choose a de-caffeinated option, contain some caffeine. Caffeine can also have a mild diuretic effect and can hinder your hydration.

Dehydration, a state whereby the body lacks fluid, may cause you to feel thirsty or pass urine which is darker in colour or stronger smelling. You might also feel sluggish, light headed and or have a dry mouth.

Children and the elderly, are more at risk of becoming dehydrated. Signs that might give your doctor cause for concern is if children are becoming drowsy, having fewer wet nappies or if they are breathing more quickly. Older people often may not realise that they are dehydrated and confusion is a common presentation of dehydration in the elderly.

Patients experiencing vomiting, diarrhoea or sweats as a result of a fever can become dehydrated quickly unless they are able to replace the extra water lost from the body.

*Originally written for The Independent July 2015, rewritten for blog post March 2017.

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