We cannot live without water. It is critical for proper body and brain function. It enables our blood to flow properly and helps us stay energized.

    The good news: "Most people can handle mild amounts of dehydration,"says Dana S. Simpler, MD, an internist in private practice. “The body regulates fluid balance through a number of complex pathways, including reduced urine production, increased reabsorption of water in the intestines and thirst—which prompts rehydration.”

   Simpler is careful to point out the difference between being low on fluids and clinical dehydration. “Dehydration mainly occurs with illnesses such as fever, diarrhea and vomiting where excessive fluids are lost and not being replaced or in a sport situations/hot weather where excessive perspiration is not being replaced," she explains.

    So how much water do you need? And what about that old standby recommendation to drink eight 8-ounce glasses of water per day?“ It is an oversimplification of what the body actually needs,"says Simpler. "There is really no optimal amount of hydration." The weather, your diet and exercise habits are all a factor in how much water you need. Some days you will need more fluids, other days less.

    Those fluids can come from virtually any drink and even some foods. Milk, smoothies, and juice drinks count. Caffeinated beverages, such as tea, coffee and energy drinks, count, too. Eating water-containing foods, including tomatoes, cucumbers, watermelon and oranges, is also a great way to up your fluid intake.

    All things considered, it makes sense to clue in to symptoms that can signal the need for more fluids. Here are a couple signs to pay attention to: you are thirsty (it may seem obvious, but a dry mouth and how thirsty you are do correlate to how hydrated you are), you are lightheaded or worn out (if you feel dizzy, you may be dehydrated), and your urine is extra dark (concentrated urine isa clear indicator that you are dehydrated. It means your urine has more waste in it).

(Adapted from http://www.safebee.com/health/7-signs-you-need-drink-water)

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