Energy comes from food, but the ability to make good use of this energy comes from keeping the body well hydrated. Efficient mental and physical function relies on water being available to all body and brain cells. Students do better in tests and examinations when they drink water through study sessions. A glass every hour and a half is good. Frequent sipping from a drink bottle with a sipper is a method some people are finding useful.
People perform better in examination rooms when they have had a glass of water beforehand.
It should be noted that pure water does not increase urine production nearly as much as coffee, tea, or alcohol. Schools and universities are starting to allow examinees to take a water bottle into examination rooms for the same reason that long distance runners and cyclists are encouraged to take water during racing. Drinking water frequently is a vital factor in the search for ways to increase the power of the mind. Fortunately, many businesses, schools, hospitals, and factories are now providing water purifiers and encouraging people to drink more water for improved mental and physical productivity. This heavy duty dual system has the benefit of a 5 micron pre-filter to remove silt, rust, hair and other large particles, protecting the second stage cartridge from excessive fouling.