How much water should I drink a day?
When it comes to the optimum amount of water to drink each day, everyone seems to have a different opinion. So should we be drinking 6-8 glasses, two litres, or even more? Do other liquids besides water count? And what are the warning signs that you’re drinking too little water? We asked registered nutritionist Kerry Torrens for her expert opinion.
What are the benefits of drinking water?
When you stop to think that more than two thirds of your body is water, it’s obvious how important it is to stay well hydrated. Hydration is needed for digestion, for our heart and circulation, for temperature control and for our brain to work well. Water is, without doubt, the single most essential component of the human body.
Drinking water may boost mental performance
Research suggests that losing as little as 1% of your body weight in fluid may reduce mental performance, as well as potentially inducing fatigue and headache. This mild level of dehydration can easily occur over the course of a normal day’s activities, which highlights how important drinking little and often is for your health.
Drinking water may boost mood
Being dehydrated can also affect our mood and mental wellbeing, with studies suggesting that energy levels, cognition and emotions may all be affected.
Drinking water may boost physical performance
If you exercise, some studies suggest that as little as a 2% loss in your body’s water content may impact how well you perform physically. Dehydration may compromise your body’s ability to control its temperature, increase feelings of tiredness and unsurprisingly, make exercise more difficult. However, research in this area is conflicting. One small study which kept athletes in the dark about their hydration status showed that dehydration made no difference to their performance. Clearly other factors besides temperature, climate and endurance also play an important role here.
What are the symptoms of dehydration?
Thirst and passing dark-coloured urine are key signs that you may be dehydrated, as well as feeling lethargic, dizzy or having a dry mouth and lips. If you’ve been ill with diarrhoea and vomiting or fever, you can become dehydrated very quickly unless you replace the extra water lost from the body. In certain circumstances rehydration solutions can be useful because they help to replace the water, salts and minerals that your body has lost. If you are experiencing this, the NHS recommends that you consult a pharmacist who may recommend oral hydration sachets, and speak to your GP if your symptoms don’t improve with treatment.