How many glasses of water should a 50 year old woman drink a day?

6 to 8: Would be great.

Maintenance : Depends on activity , perspiration rate, relative humidity and other things. But for a sedentary female, your h20 intake should be about 2.2 liters daily (about 75 ounces or 8-10 8 ounce glasses/day) versus a sedentary male, which is about 2.5 l per day.

Range: Not less than 1 l and not more than 2 l. Water is clearly better than sugar "stuff". Not enough: kidney trouble too much: frequent visits to the bathroom.

Enough to pee: Any food item you ingest is likely to contain some fluid value.Some, like applesauce or peaches can have as much as 95%, while vegies are usually 60%. As long as you pee every 6 hours or so your intake is adequate. Trying to reach some artificial goal of "glasses" ( ?size,frequency) you are wasting time & effort you could spend enjoying life.