Without any water intake, the human body can last for about 3 days at most. Water is the source of life. If people don't drink water on the first day, they will feel dry mouth, less urine, large appetite and fatigue. If you don't drink water the next day, people will be dehydrated, dry skin, dizziness and organ failure. Article 3 If you don't drink water, your body will have coma, organ failure, collapse, headache and other symptoms. Adults need about 1500~2500ml of water every day. Water can promote the discharge of waste and regulate the temperature of human body. Water is the main component of body fluids.