When I advise clients on nutrition, I’m often asked about water. How much? When? How? What if?…
We need water to survive and our bodies are made up of more than two thirds of the stuff. It makes our bodies function, improves circulation, regulates temperature and keeps the mind functioning properly. Recent research has also suggested that losing as little as 1% of water in body weight, will affect mental performance. Fatigue and headaches are also common through mild dehydration and it’s easy to lose 1% during daily activities, hence the best way is to continuously drink throughout the day.
Drinking for exercise
There are lots of conflicting studies on this and I can only comment on my own experience. Some studies state that losing 2% of water will impact how you perform. Personally, I say replace what you lose through sweat. Some days when I’m working intensely with clients and my own training, I’ll drink 5 litres or more, yet I’ll still only visit the loo once or twice in that time.
Symptoms of Dehydration
When I was in the military, there were always posters by the urinals. The posters had colour charts that you could visually check there and then your urine stream. I’ve been out of the RAF now for nearly 7 years, yet I still picture these charts and still live by what a medic told us on arrival into Afghanistan; “You must pass clear urine once per day at least”. There are many other signs along with dark urine such as dry mouth, headaches and fatigue. If you have recently been vomiting or had diarrhoea, you may also need to replace lost salts and minerals so it’s good to speak to a pharmacist. Always consult your GP if you have any concerns that you might be dehydrated and are not seeing improvements after consuming water.
So how much should we drink per day?
This has been heavily studied for many years. Personally, I advise at least 1.5 litres a day but more if exercising. Drink little and often throughout the day and then drink before, during and after exercise. In the UK, the Eatwell guide suggests 6-8 glasses of water a day. This is based on a healthy diet too though. It’s suggested that we get 20% of our water need from the food we eat such as fruit and veg. However, if you’re not getting the recommended 5 a day, this may not be the case.
Other liquids also count for you daily allowance. Yogurts, milk, smoothies, juice, protein shakes, tea and coffee all count. However, caffeinated drinks do make the body produce more urine so do not allow on this alone to keep hydrated. Also, fruit juice contains lots of free sugars/simple carbohydrates which again, are not great for overall health and therefore this should be limited.
To conclude, I’d recommend drinking 1.5 litres of water per day, more on training days or if in hot weather. Eat lots of fruit and veg and limit tea and coffee. If your urine is dark, you need to drink more and aim for clear or light-yellow colour. If you often get headaches and feel generally fatigued, you may be able to fix some of this by stating hydrated. If you have any concerns always seek advice from a Pharmacist or GP.