Topic summary contributed by volunteer(s): Lindey

Impacts of Dehydration on Health

Drinking enough water is very important to human health. Studies suggest that dehydration may be associated with falls and fractures, heatstroke, heart disease, lung disorders, poor kidney health, bladder and colon cancer, urinary tract infections, constipation, dry mouth, cavities, decreased immune function, and cataract formation.

Children also suffer the effects of dehydration. Studies have shown many children are in a state of mild, voluntary dehydration at the beginning of the school day. Significant improvement in their cognitive performance happens by simply having a drink of water.

Reversing Dehydration

Since our brain is 75% water, hydration is extremely important for brain health. When we get dehydrated, our brain actually shrinks. Even mild dehydration has been shown to change brain function. Effects of fluid deprivation include increased sleepiness and fatigue, lower levels of vigor and alertness, and increased confusion. Drinking water can immediately reverse these symptoms, because water absorption happens rapidly – within five minutes from mouth to bloodstream. For faster hydration, cold water is absorbed about 20% faster than warm.

We can also get water from other beverages, including caffeinated drinks. Black tea has been shown to offer similar hydrating properties to water, and drinking tea can include antioxidants to improve health, without adding calories. Drinking alcoholic beverages can lead to dehydration, as well as other health issues.

An easy way to tell if you are dehydrated is to drink three cups of water. If your output is less than one cup, there’s a good chance you were dehydrated. Researchers recommend 4-7 cups of water per day for women and 6-11 cups per day for men.

The information on this page has been compiled from the research presented in the videos listed. Sources for each video can be found by going to the video’s page and clicking on the Sources Cited tab.

15 videos

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All Videos for Dehydration

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