glass of water

What’s behind the ‘drink 8 glasses of water a day message? We keep hearing this and while it sounds like it might be a good idea, do we understand why?

Facts About Water & Your Body

The body is made up 75% water. About 10 pints of that water is within your blood circulation. But think about how much you weigh, and the fact that 75% of your weight is water. Where is the rest of the water?

There are 2 other reservoirs of water within your body. One is within the cells that make up your body and the other is surrounding the cells (between the cells and the blood vessels, this is called lymph).

The lymph, which is mostly water, bathes the cells in liquid. It floats nutrients from the blood circulation into the cells. It works the other way too. Waste from the cells floats over into the blood circulation so it can be taken away and removed from the body.

Thirst is a Poor Indicator to Your Level of Hydration 

As we get older our thirst mechanism declines. For example, when we feel thirsty at age 40 our body is more dehydrated than it would have been at age 20 with the same level of thirst experienced. Also, the same level of thirst at age 60 means an even greater level of dehydration. The end of this spectrum is clearly seen in very old people in nursing homes. Very old people will say they are not thirsty despite not having had a drink all day. It’s easy for the very old to get severely dehydrated.

Our thirst mechanism starts to decline in our 20’s and other signals our bodies give us when it needs , e.g. hunger, are misinterpreted. The result is we don’t drink enough water.

Effects of Dehydration

If water is short there is a hierarchy mechanism at work in the body, with the brain sitting right at the top. For adequate water to get to the brain the blood circulatory system must have adequate volume. If water is not in abundance it will ‘borrow’ some from the lymph. The lymph in turn will ‘borrow’ some from the cells.

The result is dehydrated cells. Have you ever had a hangover? How well were you able to function in that state? Cells can’t function properly when they are dehydrated. If the lymph is running low on water it can’t function properly either It can’t take goodies to the cells and remove toxic waste products away from the cells efficiently.

What’s the result of all of this? Well lack of energy for one, but on a more serious side this can set the stage for all sorts of illness the longer it goes on.

While I was researching water I came across a patient comment about doctors. It mentioned that we rarely ask about fluid intake. “How true” I thought. This is no doubt due to the fact that we were not taught about the importance of water at medical school.

Thank you for reading. Please get yourself a glass of water and tell me what you thought of this.


Uber Health to you 🙂