There is much debate regarding the nutritional value of coconut water. It is a good sport drink supplement, but still, water is healthier.
Per equal amounts, coconut water has more sugar and less sodium than many beverages. This makes it healthier than a sports drink with a higher level of potassium.
People who drink coconut water usually do so for the taste. It is a salty sweet mix that can help a person who has been sweating a lot. This loss of fluid might be due to extreme exercise like marathons or simply living in a hot climate without air conditioning.
One thing that a person has to remember is that there is no miracle beverage out there. The body needs water in whatever form it can get it for survival. Aside from that, type of fluid consumed is usually a matter of choice. It is always healthier though to consume low sugar drinks.