Why the amount of water present in one's body is measured from the amount of fat?

Please find below the solution to the asked query

Water is an important constituent of our body. All the organs of body contain different quantity of water. The fats have little amount of water while muscles contain more amount of water. More the amount of fat in body less is the amount of water as fats contain less water. Hence, amount of water in body is used to measure the amount fat in body.
        
Hope this information will clear your doubts about the topic.
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