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View Full Version : Water, do we really need 8 glasses a day


Taterhead
04-21-2006, 12:45 PM
I just started reading "The Glycemic Load" by Rob Thompson, and this below is straight from the book page 67. I find it a very interesting read so far.

"Water is great but do we really need 8 glasses a day?"

Only recently in the span of human existence have people had containers to transport water or cups to drink it from. Prehistoric humans had to get down on there hands and knees to sip water from pools and streams. THEY DIDN'T HAVE BEVERAGES WITH EVERY MEAL. They went for days without any liquids at all. Nobody knows where the recommendation to drink eight glasses of water a day came from. There are no studies in the medical literature showing any benefit at all from drinking more water than you are naturally inclined to. Indeed, there's plenty of water in fruit, vegetables,meat and dairy products, not to mention other beverages. Many people do just fine on a glass or two of liquid a day. The idea that you should drink more water than you are naturally inclined to probably stems from the notion that it washes toxins out of the body, like running water over a bowl of lettuce to wash away the dirt. In fact, water in excess of what you need to survive doesn't even go into the cells of your body. You would die of water toxicity if it did. It goes directly to your kidneys and out in your urine.

Your body has powerful mechanisms for regulating water balance. The slightest decrease of your body's water content triggers compelling thirst and an outpouring of the hormone vasopressin, which provokes thirst and sharply reduces the amount of water that goes out in your urine. Unless you have a rare vasopressin deficiency, there's no need to consciously try to regulate your fluid intake. Your natural thirst mechanisms do the job just fine.

The simple-minded notion that filling your stomach with water makes you eat less is completely off base. Stretching the stomach with liquids just makes it empty faster and speeds the absorption of glucose. In fact, several things about the way liquids affect digestion suggest that excess water may actually promote weight gain. Laboratory animals deprived of water sharply curtail their food intake. Beverages consumed with a meal liquefy stomach contents and quicken their entry into the bloodstream. The more liquefied food is, the higher it raises blood glucose levels and the less it suppresses appetite.

My advice is that you make water your thirst quencher of choice (humans are the only animals on earth that drink anything but water), and let your thirst decide how much you drink.

gator8me
04-21-2006, 02:19 PM
Very interesting. I wonder then why I feel so much better when I get at LEAST 8 to 10 glasses of water in per day. I also lose weight easier when I keep up with my water intake. I agree though that we shouldn't drink a whole lot WITH our meals though. I never drink anything while eating and it seems to help my digestion to do it that way.
Ally

Mitra
04-21-2006, 02:20 PM
I haven't been able to find a reference in PP for the recommendation to "drink till you float," so this is a personal view.

I had a look around the internet recently, and came up with this advice from Water UK (http://www.water.org.uk/home/water-for-health/ask-about/adults).

It suggests that the water requirement for average weather is 4% of bodyweight, which includes water from the breakdown of carbs, fat and protein in food, water in food, and all drinks. Their table estimates that for an average kind of diet about half of the water requirement would need to be from drinks. If your diet is mainly shakes and soup it will be less; if your diet is jerky and dry foods, then you'll need to drink more. If the weather's hot, dry or windy, you're pregnant, or you're in the early days of eating low carb, then you'll need more.

Taterhead
04-22-2006, 01:48 PM
Great read Mitra, thanks