The benefits of H20

In one study in women, a fluid loss of 1.36% after exercise did impair both mood and concentration, while increasing the frequency of headaches
According to two studies, drinking 500 ml of water can temporarily boost metabolism by 24-30%
The researchers estimate that drinking 2 liters in one day can increase energy expenditure by about 96 calories per day.
It may be best to drink cold water for this purpose, because then the body will need to expend energy (calories) to heat the water to body temperature.
One study showed that dieters who drank 500 ml of water before meals lost 44% more weight over a period of 12 weeks, compared to those who didn’t.