Research indicates that mild dehydration (even one or two percent lower hydration level of hydration than optimal) can negatively affect your mood and ability to think.
A small study conducted on 25 women and published in the Journal of Nutrition found that being dehydrated can take a toll on your mood and cognitiive function. The color of your urine is a good indicator of your level of hydration. The lighter the color the better the level of hydration and vice versa.
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