The human body needs an average of 30g of water, per day, per kilogram of body weight, which corresponds to a volume of water varying between 2.5 and 3 liters per day.
An American study by the American Chemical Society found that adults who drink water before each meal consume less calories during the meal, and therefore lose weight more easily.
Dehydration would impede the proper functioning of our brain, which would lead to problems of concentration or memory losses.
Video: Take stock of your water needs! http://vimeo.com/34212246
Sources : Docteur Bonne Bouffe,