"Staying hydrated" is one of those phrases we use more of we we grow older, right?! But, it's important.... According to Prevention magazine, staying hydrated may help strengthen your immunity as well. "Your mucous membranes and the immune cells in their secretions defend against cold viruses, and they can't work as well if you're dehydrated." It's just the doctor told you~drink your fluids! How much fluid intake for you each day? Divide your weight into 3, and that tells you how many ounces of fluid you need, plus an extra glass of water for every cup of coffee or alcoholic beverage.