According to ESchool Today, humans need the sun, water, food, air and a constant temperature in order to survive. Humans need the sun as a source of heat and light.
Water is an essential part of survival, and the Mayo Clinic shows evidence to suggest that men need up to 3 liters per day while women need 2.2 liters per day. The Mayo Clinic also states that without an adequate amount of water, the body can become dehydrated and unable to carry out normal functions. Food is also necessary for the body to keep going, as it helps to absorb nutrients for energy, according to English Online. Food helps the body repair muscles, fight off diseases and stay healthy.
Air, or oxygen, is what humans need in order to be able to breathe. The oxygen humans intake helps turn food into energy and get rid of carbon dioxide in the blood, as stated by the Astonishing Science Spectacular Museum.
Lastly, Cool Antarctica says humans have to maintain a constant body temperature or else the amount of water loss is increased, and humans run the risk of getting hypothermia or suffering from a heat stroke or a breakdown of the central nervous system.