If stranded on a deserted island with no freshwater it is not advisable to drink sea water why not?

water from the sea is salted so it dehydrates you quickly

Body gets dehydrated after drinking salty sea water

Explanation:

Human urine consists of salt that is lesser in quantity as compared to the salt content with in salty sea/ocean water.

Generally, if we drink much of salty water our body tries to remove excess salt through urination thus a large amount of water is expelled out of our body. As compared to the water taken in, the rate at which it is removed becomes much faster.

Hence, after drinking salty water our body gets dehydrated and in severe cases excess of sodium causes coma, organ failure and even death