"What's that you say - you're not feeling well? Drink plenty of water!"
"Everyone should drink 8 to 12 glasses of water a day."
"By the time you're thirsty it's too late."
"Always carry water with you at all times - always - and drink constantly throughout the day."
"Coffee dehydrates you, and anything that's not plain water will dehydrate you."
These are some examples of the types of beliefs I've heard people swearing by since some time in the 1990s to my recollection. I don't have any data to show whether people were so adamant about drinking water in the 1980s and earlier but I strongly suspect they were not.
Somehow, at some point, it's as though people became convinced that we are all dry sponges that must be constantly doused - constantly. It's understandable that people would believe so strongly that we all need to drink a lot more water: for one thing, it is far more important than food or almost anything else for our survival -- also, water just has that pure, clean, healing imagery to it doesn't it? I too used to believe so strongly in drinking water I figured you can't possibly get too much of the good stuff. Gradually, however, I became convinced that people might be way too zealous about it.
Nowadays, I have returned to my normal non-water anxiety self after having read more about it including the fact that plenty of things can hydrate you besides water -yes even coffee!
Today, I stumbled upon more information to debunk what is starting to seem almost like a "water myth":
Metabolism Myth #5
Is it true that by the time you're thirsty, you're already dehydrated?
Posted by Dr. Mark Dedomenico on Thursday, July 9, 2009 5:16 PM (MSN.COM)
How many of you have heard that by the time you are thirsty, it's too late, you're probably dehydrated? Well, let’s see what's really going on when your body signals it's thirsty.
Plasma osmolality is a measure of the concentration of substances such as sodium, chloride, potassium, urea, glucose, and other ions in blood. When you get an increase of plasma osmolality, this means substances in the blood such as sodium have become more concentrated, decreasing the amount of fluid or water in the blood.
Less than a 2 percent rise in plasma osmolality—that's not very much—will elicit thirst. However, it takes a 5 percent rise in your plasma osmolality to indicate true dehydration. Therefore, you could dine out on a high-sodium meal and make yourself extremely thirsty, but this doesn't mean you’re dehydrated. You can get significant increases in thirst without extreme concentration changes in your body fluid.
On the other hand, instances where “thirsty is too late” include water immersion and dehydration in the elderly. Water immersion is where you are plunged in cold water intermittently or for long periods at a time at 60°F or below. In some cultures such as in Russia, they perform such plunging to increase blood flow. Water immersion suppresses thirst response even though you may be dehydrated. And as for the elderly, unfortunately, as we age, our thirst response to dehydration becomes less sensitive, resulting in many elderly not meeting their fluid needs.
So don’t worry; this is just one more of those myths. Just because you're thirsty it doesn't mean you're severely dehydrated or that you've waited too long to hydrate yourself. You may have just had a high-sodium meal or increased your potassium intake by eating bananas, creating a greater concentration of ions in your blood, triggering your thirst.
Who knew? Definitely aim to drink consistently throughout the day. Water is the best hydrating agent and truly is the fountain of youth.
Nowadays, I have returned to my normal non-water anxiety self after having read more about it including the fact that plenty of things can hydrate you besides water -yes even coffee!
Today, I stumbled upon more information to debunk what is starting to seem almost like a "water myth":
Metabolism Myth #5
Is it true that by the time you're thirsty, you're already dehydrated?
Posted by Dr. Mark Dedomenico on Thursday, July 9, 2009 5:16 PM (MSN.COM)
How many of you have heard that by the time you are thirsty, it's too late, you're probably dehydrated? Well, let’s see what's really going on when your body signals it's thirsty.
Plasma osmolality is a measure of the concentration of substances such as sodium, chloride, potassium, urea, glucose, and other ions in blood. When you get an increase of plasma osmolality, this means substances in the blood such as sodium have become more concentrated, decreasing the amount of fluid or water in the blood.
Less than a 2 percent rise in plasma osmolality—that's not very much—will elicit thirst. However, it takes a 5 percent rise in your plasma osmolality to indicate true dehydration. Therefore, you could dine out on a high-sodium meal and make yourself extremely thirsty, but this doesn't mean you’re dehydrated. You can get significant increases in thirst without extreme concentration changes in your body fluid.
On the other hand, instances where “thirsty is too late” include water immersion and dehydration in the elderly. Water immersion is where you are plunged in cold water intermittently or for long periods at a time at 60°F or below. In some cultures such as in Russia, they perform such plunging to increase blood flow. Water immersion suppresses thirst response even though you may be dehydrated. And as for the elderly, unfortunately, as we age, our thirst response to dehydration becomes less sensitive, resulting in many elderly not meeting their fluid needs.
So don’t worry; this is just one more of those myths. Just because you're thirsty it doesn't mean you're severely dehydrated or that you've waited too long to hydrate yourself. You may have just had a high-sodium meal or increased your potassium intake by eating bananas, creating a greater concentration of ions in your blood, triggering your thirst.
Who knew? Definitely aim to drink consistently throughout the day. Water is the best hydrating agent and truly is the fountain of youth.
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