Can't figure out inner skin dryness/dehydration.

My skin is soft to the touch on the outside but when I press a finger or nail into my skin (face, hands, feet, legs) the skin stays 'depressed' for a while. Also my skin looks very flat like there is no layer of moisture below the skin, its not plump like it used to be. Ive tried increasing fatty acids, tons of water, and Sea Salt . What is going on here?