The human body depends on water for the maintenance of good health and survival. Different people need different amounts of water to stay hydrated. Most healthy people can stay well hydrated by drinking water and other fluids whenever they feel thirsty.
The exact amount of water in the human body varies by age, gender, physical activity, and BMI. Water is so important to human survival and function in that more than half of human body weight is made of water. This implies that over 50% of your total body weight is contributed by water.
At birth (neonates and infants), about 65% to 75% of the total body weight is made up of water. The percentage of total body water declines as a child grows into adulthood. This is partly due to increased fat deposition and bone development during growth.
When described in liters, the average amount of water in an adult male is about 42L, which is about 11 gallons. You may wonder where in your body is all this water stored. The water is distributed within and outside the cells that make different organs in your body. About 73% of your brain is made up of water, about 70% of your heart is water, and 90% of your blood is water (in the form of plasma, the liquid portion of blood).
Water is essential for normal body function. It is an important medium for the delivery of key nutrients required by body cells for survival. It facilitates food digestion, absorption of nutrients from the intestines, transport of nutrients in the blood to other parts of the body, and breaking down of nutrients to yield energy for our day-to-day activities like walking, talking, and running.
Body water also helps in excreting waste products, mainly in the form of urine. Body water also plays vital role in regulating your body temperature through sweat production, which cools the skin when the core temperature begins to rise. In some parts of the body, water also provides cushioning function. For example, the fluid surrounding the brain and that which surrounds the developing fetus (in a pregnant woman) provides a protective cushioning function to the sensitive tissues. The water in the joints helps lubricates the joints and prevent pain that may arise from friction.
The importance of body water for human survival cannot be overemphasized. Therefore, maintaining an adequate water level is paramount. Getting enough water depends on the food and beverages you consume each day. The ideal amount of water you should consume varies greatly, depending on factors such as age, body weight, health, environmental temperature, and activity level.
Your body naturally tries to maintain healthy water levels by excreting excess water in urine. The more the water intake, the more the urine that is produced in the kidneys. However, when the amount of water you lose exceeds your water intake level, you risk becoming dehydrated. It is important to note that babies, children, and the elderly are more at risk of dehydration.
Water is lost through urination, sweating, and even breathing. You lose water faster in hot weather, during intense physical activity, or if you have a fever. Vomiting and diarrhea can also lead to rapid water loss. Be sure to actively drink plenty of water to avoid becoming dehydrated.
Dehydration presents with symptoms such as dark-colored urine, decreased urination, headaches, weakness, dry mouth, and decreased skin turgor. The dried skin in a dehydrated person doesn’t “bounce” back when pinched. Dehydration may also present with heart racing (rapid heart rate), hyperventilation (rapid breathing), confusion, dizziness, fever, and loss of consciousness.
People of all ages can suffer from dehydration, however, infants and children are particularly prone and more vulnerable to dehydration. You should seek immediate medical attention the moment your child falls sick. Dehydration commonly accompanies a lot of childhood sicknesses such as fever, vomiting, and diarrhea. Watch out for symptoms of dehydration in your infants. They may have a sunken soft spot on their head (sunken fontanelle), drowsiness, few or no tears when they cry, have cold and blotchy-looking hands and feet.
Oral rehydration salts are commonly used in the management of dehydration (especially in its mild to moderate forms). Make sure you adhere to prescribed instructions for the administration of oral rehydration salt solutions. administering small but regular sips of the fluid is more effective because it allows the body to absorb as much fluid as possible. Children should not be given fizzy drinks or fruit juice as they may increase the child’s chances of having diarrhea, thereby losing more fluid and complicating the dehydration.
Daily recommended water intake for adult males and females is 2.7 and 3.5 liters respectively. Keep in mind that you can consume water in a variety of ways. Although plain water is best for staying hydrated, other drinks and foods can help, too. About 20% of your daily water intake comes from the food you eat (especially fruits, vegetables, milk, soup, and tea). A glass of orange juice or a hot tea beverage is also a good source of your recommended daily water intake.
Taking caffeinated drinks (for example, coffee and black tea) can contribute to your daily water intake. A moderate amount of caffeine (400 milligrams/day; about 6 teaspoons of instant coffee a day) isn’t harmful to most people. Caffeine can be found in your coffee, green/black tea, and energy drinks. To experience the best result of staying hydrated, it will be better if you limit your intake of caffeinated beverages because it could increase your rate of water loss by causing excessive urination.
Health conditions such as diabetes, urinary bladder infection, and kidney disease increase the odds of dehydration. Other risk factors include heat-related injuries (heat stroke), fever, electrolyte imbalance, vomiting, diarrhea, loss of blood (hemorrhage), pregnancy, breastfeeding (lactation), and old age.
The risk of dehydration is similarly higher in people who exercise at a high intensity (especially in a hot environment) for too long or those working in a hot/humid environment. During exercise, you tend to perspire more, thereby increasing water loss and your chances of dehydration.
Sports drinks can be helpful if you’re planning on moderate- to high-intensity exercise for an extended period of time. These fluids contain carbohydrates and electrolytes that can increase your energy and help your body absorb more water. Note that energy drinks differ from sports drinks in that energy drinks contain a large quantity of sugar, caffeine, and stimulants.
As long as you make water and fluid intake a part of your day — stepping up your water consumption on hot days and when you’re exerting yourself physically — you should be able to maintain healthy fluid levels and avoid the potential health problems that come with dehydration.
If you are finding it difficult to keep yourself hydrated, some basic strategies you could adopt to improve your hydration habit include keeping a bottle/jug of water with you throughout the day, adding a slice of lemon to your plain water (to make it taste better), and getting used to taking small sips of water on an hourly basis (scheduled water intake).