About 71% of the Earth’s surface is water-covered. While the oceans hold about 96.5% of all of Earth’s water, the liquid is also found in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers. And in you.
Up to 60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, 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 at 31%. Our blood? That is a whopping 90%. Therefore, drinking the transparent liquid isn’t just advised, it is imperative to do so.
Keeping hydrated is crucial for health and well-being, but many people do not consume enough fluids each day. Perhaps it is the ubiquitous nature of water that means drinking enough each day is not at the top of many people’s lists of priorities.
The Benefits (and Necessity) of Drinking Water
From the start, it is important to dispel a myth. And that myth is that there is a required water intake that a person needs in one day. The truth is that there is no universally agreed quantity of water that must be consumed daily. It differs from doctor to doctor, from person to person. What is not in dispute, however, are the benefits ascribed to drinking water.
To function properly, all the cells and organs of the body need water. The liquid lubricates the joints – cartilage found in joints and the disks of the spine contains around 80 percent water. Long-term dehydration can reduce the joints’ shock-absorbing ability, leading to joint pain. Water also forms saliva and mucus which helps us digest our food and keeps the mouth, nose and eyes moist. This prevents friction and damage. The life-giving liquid delivers oxygen throughout the body through our blood which, as mentioned above, is more than 90 percent water. It also boosts skin health – with dehydration, the skin can become more vulnerable to skin disorders and premature wrinkling – and it cushions the brain, spinal cord, and other sensitive tissues. Dehydration can affect brain structure and function. It is also involved in the production of hormones and neurotransmitters. Prolonged dehydration can lead to problems with thinking and reasoning.
Aside from these important factors, water also regulates body temperature as it is stored in the middle layers of the skin and comes to the skin’s surface as sweat when the body heats up. (Some scientists have suggested that when there is too little water in the body, heat storage increases, and the individual is less able to tolerate heat strain.) Of course, our digestive system depends on it to ensure that the bowel works properly. Dehydration can lead to digestive problems, constipation, and an overly acidic stomach. This increases the risk of heartburn and stomach ulcers. Furthermore, water intake helps to maintain blood pressure – a lack of water can cause blood to become thicker, increasing blood pressure. Our airways need it to breathe easily because when we are dehydrated, they are restricted by the body in an effort to minimize water loss. This can make asthma and allergies worse. And it also dissolves minerals and nutrients which makes it possible for them to be carried to different parts of the body.
Water and Kidney Health
If all of these reasons aren’t enough to illustrate the importance of water, perhaps understanding how it prevents kidney damage is. And water is a key component of protecting these organs.
The kidneys play a key role in balancing fluid levels in the body. Every day, the kidneys filter around 120-150 quarts of fluid. Of these, approximately 1-2 quarts are removed from the body in the form of urine, and the rest is recovered by the bloodstream. If the kidneys do not function properly, waste products and excess fluid can build up inside the body. Untreated, chronic kidney disease can lead to kidney failure. The organs stop working, and either dialysis or kidney transplantation is required. The kidneys need water to function properly and process the fluids. Without the water, it is an operational meltdown and serious risk – including death – is at hand.
Aside from filtering processes related to the kidneys, drinking water is also a simple and easy way to reduce the risk of developing urinary tract infections (UTIs). These are the second most common type of infection in the body and account for nearly 10 million visits to healthcare providers in the US each year. If infections spread to the upper urinary tract, including the kidneys, permanent damage can result. Sudden, or acute, kidney infections can be life-threatening, particularly if septicemia occurs. While drinking water cannot cure a UTI – an antibiotic is required – it can reduce the risk of one and also help to treat an existing infection.
The leading cause of kidney stones is a lack of water, and they can also increase the risk of chronic kidney disease. In November 2014, the American College of Physicians issued new guidelines for people who have previously developed kidney stones. The guidelines state that increasing fluid intake to enable 2 liters of urination a day could decrease the risk of stone recurrence by at least half with no side effects.
Dehydration happens if we use and lose more water than the body takes in. It can lead to an imbalance in the body’s electrolytes. Electrolytes, such as potassium, phosphate and sodium, help carry electrical signals between cells. The kidneys keep the levels of electrolytes in the body stable when they function properly.
When the kidneys are unable to maintain a balance in the levels of electrolytes, these electrical signals become mixed up. This can lead to seizures, involving involuntary muscle movements and loss of consciousness.
In severe cases, dehydration can lead to kidney failure, which can be life-threatening. Possible complications of chronic kidney failure include anemia, damage to the central nervous system, heart failure, and a compromised immune system.
Losing Water
During everyday functioning, water is lost by the body and needs to be replaced. We notice that we lose water through activities such as sweating and urination, but water is lost even when breathing. Drinking water, whether from the tap or a bottle, is the best source of fluid for the body.
Milk and juices are also good sources of fluid, but beverages containing alcohol and caffeine, such as soft drinks, coffee and beer, are not ideal because they often contain empty calories. Drinking water instead of soda can help with weight loss.
It was previously thought that caffeinated beverages had diuretic properties, meaning that they cause the body to release water. However, studies show that fluid loss because of caffeinated drinks is minimal.
Recommended Intake
There is no unilateral agreement on how much water a person should drink per day. Due to factors such as climate, a person’s activity level, and how each body uses the ingested water make it difficult to predict how many ounces or glasses are needed to maintain body functions. A magic number does not exist. However, there is a general agreement on what a “healthy” intake is. According to the U.S. National Academies of Sciences, Engineering, and Medicine, the average recommended daily intake of water from both food and drink is:
Men: 100 ounces, or 12.5 cups of fluid
Women: 73 ounces, or just over 9 cups
Fresh fruits and vegetables and all non-alcoholic fluids count towards this recommendation.
The importance of water intake to the human body can’t be underestimated. A person can survive without food for between eight and twenty-one days, depending on the body. A person can only survive for three days without water. Water is life.
Source: Medical News Today
