Heat and humidity are the two most significant environmental factors that can affect our fluid balance and thus our body water and health. Sounds logical and it is. In areas of high heat and humidity such as Florida, Georgia or the Texas gulf coast, people tends to sweat a lot. It is our body’s air conditioner.
In practice, as the sweat evaporates, it carries away heat. In areas of high humidity, however, the sweat doesn’t evaporate so we don’t get cool and the body’s reaction is to make more sweat. This obviously depletes the body’s supply of water and health will deteriorate fast if not replaced.
Cold weather can also be dehydrating but the mechanism is very different from a heat induced sweat. In a cold environment, we still lose water through our skin but may not drink enough since we do not get the sensation of sweating that triggers the thirst mechanism.
If you have ever been a long-distance air traveler, you know that high cabin pressure at high altitude can really result in fluid loss.
Consider that our breath is 100% humidified. When the plane lands, some experts estimate that the humidity has risen to about 40%. The only place it can come from is people’s breath inside. Considering health, no wonder airliners are great for transmitting air-borne germs through the cabin moisture.
Thus the flight attendants are frequently coming around with bottled water and advising us to drink.
Don’t expect the Transportation Security Administration to let you bring your own bottled water on board so bring your wallet to buy water for your hydration.
Assessing Hydration Levels
Aside from feeling thirsty, how do we test our hydration level? The color and volume of urine can be pretty good indicators.
If your first urination after crawling out of bed in the morning is light yellow, perhaps the color of pale lemonade, chances are you did a good job of hydrating yourself the day and evening before. If it is darker in color, like apple juice or darker yellow, and the volume is smaller than usual, then you didn’t drink enough the day before. If it’s red, purple or black, you should probably be in the emergency room.
Most people would assume that thirst is a good measure of hydration but they would be wrong. Thirst is not a very good indicator because there is a lag between the time we get dehydrated and actually feel thirsty. Which means, “if you are thirsty, you are probably already dehydrated”.
Aging tends to dull the thirst mechanism and this can become very serious to older people. They run the risk of dehydration because they don’t feel thirsty and if taking medications, complications can easily occur. Water and health must be closely monitored in an elder-care setting.
Regarding medications, pain meds can blunt the thirst mechanism so if taking regular pain pills, be sure to keep up with your water intake times. Of course diuretic meds will cause thirst because their whole purpose is to remove water stored in tissue to relieve edema. In this case, follow your care givers instructions on how much water to drink and when.
Another good reason to keep properly hydrated is that it tends to prevent kidney stones. If you have ever had a kidney stone or know someone who has, it is unforgettable experience you won’t want to experience again.
Over and Under Hydration
There are definite signs and symptoms of dehydration. Weight loss, confusion, a dry skin and an elevated core body temperature are all signs of dehydration. The latter is a medical emergency that can even cause death.
A function of water is to dissipate heat and if we lose such an amount of water that heat cannot be dissipated, then core body temperature rise. Our normal body temperature is 98.6 degrees and core temperatures over 106 can kill us.
Some readers may recall the October 2009 sweat lodge incident near Sedona, Arizona in which 50 people were placed in a makeshift sweat lodge for two hours.
When it was over, three people were near death. Eighteen others suffered burns from hot steam, dehydration, respiratory arrest or kidney failure. Some participants began to appear ill after about an hour and two of the participants died that night and the third went into a coma and died a week later. Anyone still think water and health aren’t linked?
Rehydration through drinking is best but our stomach and intestines can only handle 1-2 liters at a time. So, if someone lost more than that, oral rehydration will not reestablish balance.
Over hydration means taking in more water than you can possibly need. Fraternity hazing has killed kids from forced water intake because the sodium level in the body gets so diluted that cerebral edema (swelling of the brain) occurs which can cause death.
It should be clear by now that water and health go hand in hand.