Dehydrated skin is a temporary condition characterized by a lack of water in the stratum corneum (top layer of skin), whereas dry skin is a genetic skin type that lacks oil (sebum). Any skin type—including oily and acne-prone—can experience dehydration due to environmental stressors, harsh products, or lifestyle factors. 

Signs of Dehydration:
The Pinch Test: Gently pinch the skin on your cheek or the back of your hand. If it is slow to bounce back or shows fine horizontal lines, your skin is likely dehydrated.
Appearance: Dehydrated skin often looks dull and tired, with more pronounced fine lines (often called "dehydration lines") and darker under-eye circles.
Sensation: You may feel a persistent, uncomfortable tightness, even if your skin appears oily on the surface.

Core Ingredients:
Hyaluronic Acid Multi-Complexes: Modern formulations use multiple molecular weights to hydrate both the surface and deeper layers simultaneously.
Beta-Glucans: A major trend, these offer deeper hydration than traditional hyaluronic acid while also aiding barrier repair.
Polyglutamic Acid: Known for holding up to four times more moisture than hyaluronic acid, it acts as a powerful surface humectant.
Niacinamide (Vitamin B3): Essential for strengthening the skin barrier to prevent transepidermal water loss (TEWL).