Stay Hydrated

Water is easily the most important substance in the human body. It makes up 50 to 60% of our body mass, and aids in many vital biological functions, such as nutrient distribution, regulation of body temperature, and maintaining an electrolyte balance within the body. This is why many doctors place heavy emphasis on ensuring adequate hydration in order to maintain one’s health, often citing the “daily recommended intake” of eight cups as the necessary volume of water one needs to consume on a regular basis. Yet how accurate is this prescribed amount, and what happens when one fails to meet it?

The “daily recommended intake” of eight cups of water actually has no scientific research backing it up. The myth most likely originated from a statement made in 1945 by the Food and Nutrition Board of the National Research Council, which stated that “A suitable allowance of water for adults is 2.5 liters (which is approximately eight 8-ounce glasses) daily in most instances…” The truth is that the amount of water one needs to take in varies with one’s age, gender, physical activities, medical conditions, and even the climate that they live in. Because of this, there is no solid figure for how much water an individual needs to consume each day. One estimate, from the Institute of Medicine, recommends adult males consume 3.7 liters, or 16 cups of water every day. However, this figure includes sources other than pure drinking water, such as water found in food and various beverages. In the Harvard Men’s Health Watch, it is stated that the average person receives roughly 70% of their necessary daily water intake from foods and beverages. The “beverages” specified include beverages such as milk, sodas, and even caffeinated drinks such as coffee. Caffeinated beverages, despite the myths, actually provide more water for the body than they remove, resulting in net hydration.

The Harvard Men’s Health Watch recommends drinking water whenever you feel thirsty, as thirst is the most reliable indicator of the amount of water levels in the body. A separate article from the Harvard Medical School recommends having a beverage with every meal, as well as the consumption of water-rich foods such as salads, fruit, or applesauce.

It should be noted that one’s sense of thirst decreases with old age, making dehydration much more likely. This risk is further increased for those taking medications which may induce fluid loss, such as diuretics or nonsteroidal anti-inflammatory drugs. A reliable method of determining whether you are properly hydrated is by checking the color of your urine. If your urine is clear or light-yellow, then you are properly hydrated. If your urine is dark yellow or brown, then you are not adequately hydrated and should increase your daily water intake.

Failure to achieve adequate hydration will have greatly impede one’s health. General symptoms of dehydration include thirst, infrequent urination, fatigue, dry skin or a dry mouth, dizziness, confusion, and an increase heart rate. In children, symptoms may include sunken eyes, a lack of tears when crying, irritability, skin that does not flatten after being pinched and released. Dehydration is especially dangerous in warmer climates, where water is lost from the body more rapidly, and overheating becomes a greater risk. Complete dehydration is deadly for humans, as it can kill young children within several hours, while most adults will only last a few days without water.

Drinking excessive amounts of water can also negatively impact one’s health. For instance, men suffering from heart failure may cause a buildup of fluid in their lungs by drinking too much water. Men with reduced kidney function may overload their kidneys if they consume too much water. However, studies have shown that drinking extra water does help reduce the development of kidney stones in the body. According to the Harvard Medical School, drinking two quarts of water every day significantly reduces the risks of developing kidney stones. In order to stay hydrated, one only needs to drink water when they are thirsty. If all else fails, a quick check of one’s urine will determine whether you are adequately hydrated.

References:

 Kravitz, Len. Water: Nature's Most Important Nutrient, www.unm.edu/~lkravitz/Article%20folder/WaterUNM.html.

“Dehydration and Heat Stroke.” Dehydration and Heat Stroke - Health Encyclopedia - University of Rochester Medical Center, www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=85&contentid=P00828.

Publishing, Harvard Health. “How Much Water Should You Drink?” Harvard Health, www.health.harvard.edu/staying-healthy/how-much-water-should-you-drink.

Publishing, Harvard Health. “Water and Health: Follow Your Thirst.” Harvard Health, www.health.harvard.edu/staying-healthy/water-and-health-follow-your-thirst.