When one is thirsty and feels the need to drink, it is already a sign of dehydration.
Fatigue may also depend on a dehydration condition.
The body has a constant need for water, whether doing sedentary or physical work. Getting used to drinking continuously keeps the body well hydrated and keeps fatigue away.
Those factors responsible for sometimes unexpected heart attacks
Obesity is known to be an increased risk, but even getting out of bed facing harsh cold weather conditions can become a lesser-known risk condition.