Water is the life-giving element on our planet. The different phases of water help shape its surface. Its availability has enabled the evolution of living organisms, from single-celled bacteria to highly complex flora and fauna, including humans. Climate change and the careless use of fresh-water resources around the world also contribute to the decline of biodiversity and, with it, humanity’s ability to survive on planet Earth.
We cannot live more than a few days without replenishing our bodies’ water stores. The body of an average adult is composed of about 60% water. Water is indispensable for countless bodily functions and processes, it is a component of cells and body fluids, enables many biochemical reactions, serves as a transport medium for nutrients and waste, cushions our cells, structural tissues and organs, and helps regulate our body temperature.
Typical daily intake of water in adults is 2500 mL (almost 3 quarts), most of it from food and drink delivered through the digestive tract, about a tenth is produced metabolically in the process of aerobic respiration. About the same amount is removed from the body on a daily basis, most of it through the urine and sweat, some through the stools, and the rest through evaporation from the skin and respiration. The body maintains osmolality, a description of the concentration of a solution, in a narrow range. Osmoreceptors in the hypothalamus monitor osmolality and make you aware of your need for water. The hypothalamus releases antidiuretic hormone (ADH) that signals the kidneys to excrete less water. A dry mouth will also get your attention. Other important mechanisms that compensate for, and alert you to, the insufficient amount of water in your body are a decrease in blood pressure, which makes your heart work harder, and a complex hormonal system based in the kidneys to retain sodium.
Endurance exercise, high temperatures, dry air, diarrhea or vomiting, and other circumstances can contribute to rapid dehydration. Depending on the extent of dehydration, this condition can quickly turn into a medical emergency and even lead to coma or death.
Scientists and physicians do not currently agree on how to achieve and maintain optimal hydration. The need for, and loss of, water vary widely from person to person and fluctuate depending on their circumstances. Recommendations to drink a certain number of glasses of water are not supported by definitive research, which makes sense considering the enormous individual variation. So, how do you know you’re drinking enough?
First of all, I think we need to pay more attention to when we feel thirsty. We often get so busy that we consider it inconvenient to get up and drink. We may also reach for beverages other than water, such as coffee, soft drinks or alcohol, which are counterproductive if you want to quench your thirst, either because they have a diuretic effect or supply your body with unneeded sugars. Keep in mind that thirst declines with age, esp. after your middle years.
Other indications that you’re not well-hydrated are the color and odor of your urine. It is normal for your first voiding in the morning to be more concentrated. But throughout the day, your urine should be clear, have a light yellow color and not smell intensely. However, these observations can be skewed due to certain foods, supplements or medications you may be taking.
Symptoms and signs of dehydration can also include headaches, fatigue and malaise, dizziness, elevated pulse, loss of appetite, muscle cramps, confusion, etc. Your skin may look and feel dry and lose some of its elasticity. And if you experience frequent diarrhea, you may be losing more water through your stools than you realize.
If you exercise intensely or the temperatures are high (or both), your body uses the production of sweat to cool you and prevent your core from overheating. Under extreme circumstances, you can lose several liters of water per hour this way. You also lose more sodium and other electrolytes through sweating. Replenishing your body’s water and salt reservoirs can become challenging. Usually, by the time you feel thirsty, you are already dehydrated. Athletes know that they need to hydrate diligently, even before they start training or competing. So do you!
One interesting bit of information I recently came across is that just jugging water alone is not as effective as drinking water and eating fruit or vegetables along with it to maintain good hydration status. Here are some choices that can help. Fruit and vegetables that have a very high water content to begin with include water melons, cantaloups, oranges and grapefruit, apples, peaches, berries and grapes, celery, cucumbers, lettuce, tomatoes, bell peppers, cauliflower and broccoli, zucchinis and cabbage. (Be mindful that some fruit are higher in sugars, so having a wide variety is a wise strategy.) Other good hydration sources are smoothies, soups and broths, milk, cottage cheese, kefir and yogurt, coconut water.
I know people who are concerned about the frequent or inconvenient need for bathroom trips, either when out and about or at night. If you’re one of them, try to drink most of your fluid earlier in the day, skip the Weissbier or pot of tea right before bedtime, and the benefits of being well-hydrated will make up for the extra bathroom trip(s). Research has shown that urinating more actually keeps your kidneys healthy longer. Now, that alone, in my opinion, is a big incentive to drink more water and stay hydrated.
© 2019 Christiane Siebert