Water is the human body’s most important nutrient. People may survive months without any food, but they couldn’t live more than a week without water.
Water makes up 57% to 78% of your total body weight. It regulates your temperature through different mechanisms including sweating – many people believe that sweat is fat, but in fact it is water and electrolytes. Water is involved in the transport of nutrients and oxygen to the cells, it also carries waste products (metabolites) away. Every cell, tissue and organ needs water to work properly. Water helps maintain blood volume, and it helps lubricate joints and body tissues such as those in the mouth, eyes and nose. There are several factors that are good to know in order to stay hydrated:
- The thirst sensation decreases with age. Therefore, drinking water when you are already thirsty is not an optimal decision. The thirst itself is a sign of dehydration. That’s why creating a habit to drink water frequently is crucial for both adults and children.
- The colour of the urine indicates the level of hydration. A clear, transparent yellow colour means that your body is hydrated, while a dark yellow colour is a sign of dehydration. (Bear in mind that vitamins and supplements may affect the colour of the urine and make it darker.)
Information worth considering by athletes and people who work out on a regular basis:
- If you lose even as little as 2% of body weight in fluid loss your anaerobic performance may drop.
- A 3% body weight loss due to fluid loss can adversely affect your strength.
The daily water intake recommendation for adults is based on weight, activity, weather, etc. This is the formula you can use to calculate the amount of water your should drink every day.
|Activity level||Ml / kg body mass|
|Low – Sedentary lifestyle||0,3 l. / weight in kg.|
|Moderate – Exercising 3 times a week||0,4 l. / weight in kg.|
|Active – Exercising every day||0,5 l. / weight in kg.|
NB! – In case of prolonged outdoor activity and at high temperatures, the daily liquid need may increase significantly.
Children have different water needs than adults. They are less heat tolerant and may be more likely to get dehydrated, especially when being physically active. Letting thirst guide their water consumption is not the best way to keep them hydrated.
According to the American National Academy of Sciences, children’s daily water needs based on their age are:
|Age||Daily fluid intake|
|1 – 3
|4 – 8||1,4 liters|
|9 – 13+||1,9 liters|
Women who are pregnant or breastfeeding should also take into account the specifics of their needs due to the processes that occur in their bodies. According to the American National Academy of Sciences, women who are pregnant or breastfeeding should drink, as it follows:
- 2,4 liters for pregnant women
- 3 liters for women who breastfeed