Why Our Bodies Need Water
Water is of major importance to all living things; in some organisms, up to 90% of their body weight comes from water. Up to 60% of the human adult body is water. The brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%.
Each day humans must consume a certain amount of water to survive. Of course, this varies according to age and gender, and also by where someone lives. Generally, an adult male needs about 3 liters (3.2 quarts) per day while an adult female needs about 2.2 liters (2.3 quarts) per day. All of the water a person needs does not have to come from drinking liquids, as some of this water is contained in the food we eat.
Water serves a number of essential functions to keep us all going.
Source: USGS. https://www.usgs.gov/special-topic/water-science-school/science/water-you-water-and-human-body?qt-science_center_objects=0#qt-science_center_objects
Growth and Development
Not having access to safe drinking water can create an endless cycle of poor health, stunting growth and development of children especially. Proportionately to their body weight, children have much higher requirements for water than adults. If the daily intake of water is not achieved, it can cause dehydration, which may lead to permanent physical or mental damage. A loss of 15% of total body water can cause death.
Repeated infections from unsafe water, or poor sanitation and hygiene, could lead to intestinal damage, and nutrients absorbed less well by the body. Less nutrients could also mean malnutrition, stunting physical growth and brain development. A body weak from lack of water is also more susceptible to other infections, repeating the cycle and leaving long-term effects on child health and development.
Removing Waste from our Blood
Water is essential for our kidneys to function, as they remove waste that enters the body from foods and drink, then pass it through to our blood, then finally dispose of as urine. The kidneys regulate total body water and its concentration. Water will also help to keep the blood vessels open for easy traveling of blood to the kidneys.
Dehydration from lack of water will impact the kidney’s ability to dispose of waste from our bodies.
Other Functions of Water in the Body
Your blood, muscles, lungs, heart and brain are comprised mainly of water.
Water helps to regulate your body temperature through sweating and respiration, particularly in hot environments and when doing sport.
Water helps create saliva, which is necessary to break down the foods you eat. Drinking water regularly is essential to producing enough saliva, and also to helping you to digest food easier.
Drinking water helps to keep your joints, spinal cord and tissues lubricated and cushioned.
Drinking water helps to pass stools easily.
Drinking water helps your brain to work properly, such as making hormones and neurotransmitters. Dehydration has been shown to impair brain function, concentration and short-term memory. Mild dehydration can cause fatigue.
Sufficient water keeps the skin hydrated. Skin that is well-hydrated will form a stronger barrier to keeping out bacteria and other germs.
Severe dehydration can cause brain swelling, kidney failure and even seizures.