First, it's important to understand the difference between dehydrated skin and dry skin. The terms are often used interchangeably, and although they are somewhat related, there are actually a few differences
between the two. "There's both a correlation and a difference," explains Ife Rodney, MD, FAAD, of Eternal Dermatology and Aesthetics. "Typically, dry skin is a skin type, which is an absence of sebum (the skin's natural oils), and dehydrated skin is only an absence of water that can happen to anyone. Excess oil loss, which can happen with age, affects the moisture barrier that reduces water loss. So dry skin can contribute to dehydrated skin. At the same time, it's possible to be hydrated yet have dry skin."
Ope Ofodile, MD, MPH, a cosmetic and medical dermatologist at Dermatology and Surgery Specialists of North Atlanta (DESSNA), adds that dry skin is secondary to natural genetic predisposition and not fully preventable, while dehydrated skin is an acquired condition. "Clinically, they feel the same way, but often the timeline, 'dry skin all my life' versus 'dry skin later in life,' can differentiate the two," she explains.