WebMD gives us some good reasons why we need to drink water. Here are two very important reasons

1. Water Helps Energize Muscles.

 Cells that don't maintain their balance of fluids and electrolytes shrivel, which can result in muscle fatigue.

Drinking enough fluids is important when exercising. Follow the American College of Sports Medicine guidelines for fluid intake before and during physical activity. These guidelines recommend that people drink about 17 ounces of fluid about two hours before exercise. During exercise, they recommend that people start drinking fluids early, and drink them at regular intervals to replace fluids lost by sweating.

2Water Helps Keep Skin Looking Good. 

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Your skin contains plenty of water, and functions as a protective barrier to prevent excess fluid loss. But don't expect over-hydration to erase  wrinkles or fine lines, says Atlanta dermatologist Kenneth Ellner, MD.

"Dehydration makes your skin look more dry and wrinkled, which can be improved with proper hydration," he says. "But once you are adequately hydrated, the kidneys take over and excrete excess fluids."

You can also help "lock" moisture into your skin by using moisturizer, which creates a physical barrier to keep moisture in.

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