You know the rule- drink 8 glasses of water a day. (OK, I admit it- I drink that much fluid- and then some- but NOT pure water, since I need some flavor to handle the volume.)
Part of the reason we drink that volume of water is to cut down on our appetite. So, maybe we won’t be a member of the obese generation that seems to prevail today. After all, 60% of our body weight is water- and we routinely lose about 1.9 liters of water a day via our breath (humidity in expired air), our urine and bowel movements, and our perspiration. Now, there’s a new reason to insure we drink enough water. It maintains- nay, it improves, our cognitive performance!
Earlier studies seemed to suggest that dehydration decreases mental performance in adults. Other studies indicated that drinking water improved memory performance in children.
Drs. Caroline Edmonds, Rosanna Crombie, (both of the University of East London), and Mark Gardner (University of Westminster) just published the results of some new tests in Frontiers of Human Neuroscience. (Subjective thirst moderates changes in speed of responding associated with water consumption.)
In this study, 34 subjects were involved. They were required to refrain from food and drink starting at 9 PM, and then undertook testing the next morning. On one occasion, they were provided a breakfast bar and water (500 mL of water) ; the other time, they wre only offered the cereal bar. They then were provided cognitive tests- they had to push a button as soon as they saw an object on the computer screen. Those that were provided water averaged 14% faster reaction times than those who were not offered the water. (These CANTAB- Cambidge Neuropsychological Test Automated Battery- cognitive tests determine reaction times.)
This increased brain performance was even more prevalent when those tested subjects were thirsty. Presumably, the thirst sensation caused the attention of the subjects to be diverted from their assigned tasks. So, it was not surprising that their cognitive performance was hindered. It’s entirely possible that vasopressin (the hormone involved in the thirst response) may be in play, since it is associated with arousal and attention
But, this may not be entirely true- or a universal result. Because when the subjects were required to demonstrate rule-learning(memory of words) [another cognitive test], those that did not drink water performed superior to those who drank. This anomaly has not yet been explained- and will be the subject of additional research.
Moreover, we must all recognize that we can overdose on water- really! It’s called water intoxication, when that excess water we drank reduces the sodium levels in our blood. It can be caused by excess volume- and an excessive water drinking rate.
I have heard about the cognitive benefits of water and remind my mother constantly to drink some fluids. Especially since I am trying to determine the correct cause of her diminishing memory (maybe I’m in denial?). BUT I did not know that you could over-drink water. Thx for the info.
Who knows, Alessa- may be your mom was exhibiting dehydration effects. Wouldn’t that turn out to be a relief (of sorts)?
Keep me advised! (Inquiring minds want to know 🙂 )
I love water. It’s my main drink of choice. Maybe I’m an anomaly. 😉
Cathy Miller recently posted..Has Marketing Moved From Fluff to Favored?
Many people love water, Cathy. I just need mine 35F (1C) or flavored. Sometimes, both 🙂
Roy, what are your thoughts on drinking more than the eight 8-oz. glasses (64 ounces) daily? For instance, some weight loss “experts” advise overweight people to drink half their body weight in ounces of water; so, for instance, a 200 lb. person would drink 100 ounces of water.
Also, what about the so-called “Fat Flush” water recipes, per Dr. Oz and others, that call for combining certain fruits and veggies in a pitcher of water, for their fat-burning effects?
K.Lee Banks recently posted..Meeting Goals–Completed the UBC
I can’t “a priori” comment on the over-drinking of water. It would depend upon many different characteristics of the “subject”. How well do the kidneys work? What are the electrolyte levels? What’s the blood pressure? How active is the person. I could see upping the amount of water by 10%- but beyond that, I would need the whole picture.
Don’t get me started on Dr. Oz. (If he and his minions don’t stop flooding my inbox, I would be glad to flood his image with a liquid discharge of my own…)
As one of the progenitors of colon lavage, I understand the need for electrolyte balance, flushing the body of various materials, and operating in a “safe and effective” manner. I don’t see the excessive use of water as one of them. Instead, one would be better of trying the normal diet (with ample water) and a modified fast for two days (not contiguous!). It seems that this alteration of diet helps the body to NOT become adjusted to a lower calorie diet and maintain a higher calorie burn…
Here is the second article today on water, although mine is on swimming in it. As for drinking, I have found that if I am eating and try to drink between bites, I get enough. This is specially true when I eat a fruit and nut mix I concocted.
Ann Mullen recently posted..[Infographic] Senior Care: 10 Surprising Benefits to Taking a Swim
Yes, the water I advocate is far less chlorinated (one would hope)! Thanks for the visit, Ann!
I’m always trying to drink a good amount of water each day. I know dehydration has caused some problems for my father, physically. I wasn’t aware of the cognitive effects. Interesting, as my sister-in-law was telling me that she had to take a nursing certification computer test that was 4 hours and no liquid/food was aloud, including water. It seems to me that those students could really benefit from some fluids during such a test.
Darn straight, there, Suerae. that kind of rule is going to change as this data gets promulgated.
I could do with a glass of water right now, Roy. I love water too. Warm (herbal tea) or cold with lemon. I don’t really care. I just drink water all the time!
MuMuGB recently posted..A Global Village: Rickshaw In London
Glad to hear that, Mureil. We want you to remain cognitively functional. So, we can keep enjoying your blogs!
I try to remember to drink water, but I often just have tea or coffee. Your post is great. Maybe I’ll remember now!
Carol Tomany recently posted..Bad Day
Glad to serve as a memory aid, Carol. It will do your body- and your brain- good!