Good news- you can stop worrying about drinking 8 glasses of water a day! Despite the age old rule of thumb, there is no scientific evidence that 8 glasses of water daily will promote health and stave off dehydration. Rather, the amount of fluid a person needs a day-like everything else- is different based on each individual.
Some people are at higher risk of dehydration. People who get a lot of exercise, have certain medical conditions, are sick, or are pregnant need to be more aware of the amount of fluids they drink. Older adults are also at higher risk because as you age, your brain may be unable to properly sense dehydration and send the signals for thirst.
A quick test if you are concerned that you may not be drinking enough water is to check your urine. If it is consistently colorless or light yellow, you are most likely staying well hydrated. However, if it is a dark yellow with relatively little volume, then it’s time to drink up. For the average person, drink enough so that you go to the bathroom every two to four hours.