Every living thing consists of water. The human body consists of 65% water. If the body loses more than 20% of its normal water content, the person will die painfully. A human being must take in a minimum of 4 litres of potable quality of water per day in order to carry on the life process. Whatever the nutrients (food substances) a person takes in, it is the water that dissolves them and carries them to all parts of organism, which through bio chemical reactions are converted to energy.
The 1981 report of World Health Organization, Geneva reports "Water collected for domestic use often becomes recontaminated or further contaminated by unsafe consumer storage and handling practices at the household level and is at the high risk by various pathogenic viruses, bacteria and parasites causing infectious diseases."
Therefore household safe storage can lead to dramatic improvements in drinking water quality and reduction in diarrheal disease. Assurance of drinking-water safety is a foundation for the prevention and control of waterborne diseases.
Water can affect people's health via food preparation, direct human use for drinking or for hygiene.