What is Dry Skin (Xerosis)?

Dry skin, medically known as xerosis, is a common skin condition characterized by a lack of adequate moisture in the outermost layer of the skin (the epidermis). While dry skin can affect anyone, it's particularly common in older adults and people living in dry climates.

Definition & Overview

Dry skin occurs when your skin loses too much water and oil, compromising its protective barrier function. The skin's natural barrier is composed of lipids (fats), proteins, and moisture that work together to:

• Protect against environmental irritants and pathogens
• Prevent excessive water loss (transepidermal water loss or TEWL)
• Maintain skin elasticity and smoothness
• Regulate skin cell turnover

When this barrier is compromised, the skin becomes dry, rough, and more susceptible to irritation and infection. Dry skin can range from mild, temporary dryness to severe, chronic conditions like eczema or dermatitis.

Common Symptoms of Dry Skin

Dry skin can manifest in various ways depending on factors like age, health status, location, and environmental conditions. Common symptoms include:

How Dry Skin Develops

The skin's outermost layer, the stratum corneum, consists of dead skin cells surrounded by lipids. This layer acts like a brick wall, with skin cells as bricks and lipids as mortar. Healthy skin maintains a water content of about 10-30% in this layer.

Dry skin develops through several mechanisms:

1. Reduced lipid production: The skin produces fewer natural oils (sebum), weakening the moisture barrier.
2. Impaired barrier function: Gaps form in the lipid layer, allowing moisture to escape more easily.
3. Decreased natural moisturizing factors (NMFs): The skin produces fewer of the compounds that naturally attract and hold water.
4. Environmental damage: External factors like low humidity, cold weather, and harsh chemicals strip away protective oils.
5. Inflammation: Immune responses or irritation can disrupt the skin barrier and accelerate water loss.

Dry Skin vs. Dehydrated Skin

While often used interchangeably, dry skin and dehydrated skin are different conditions:

Characteristic	Dry Skin	Dehydrated Skin
Definition	Skin type lacking oil	Skin condition lacking water
Cause	Insufficient sebum production	Insufficient water content
Permanence	Usually lifelong skin type	Temporary condition
Affected Skin Types	Primarily dry skin type	Any skin type (even oily)
Treatment	Oil-based moisturizers, occlusives	Hydrating serums, water intake

Risk Factors for Dry Skin

Certain factors increase your likelihood of developing dry skin:

Age-Related Factors

• Aging: People over 40 are more prone to dry skin as oil production decreases
• Hormonal changes: Menopause can significantly reduce skin moisture

Environmental Factors

• Living in cold, dry climates
• Low humidity environments (especially winter)
• Excessive sun exposure
• Frequent swimming in chlorinated pools

Health & Lifestyle Factors

• Medical conditions (eczema, psoriasis, thyroid disorders, diabetes)
• Medications (diuretics, retinoids, some acne treatments)
• Frequent hand washing or use of harsh soaps
• Hot, long showers or baths
• Dehydration or poor nutrition
• Smoking and alcohol consumption

When to See a Doctor

While mild dry skin can typically be managed at home, you should consult a dermatologist if:

• Your skin doesn't improve with self-care measures
• Dryness is accompanied by redness, severe itching, or inflammation
• You develop open sores or infections from scratching
• Large areas of scaling or peeling skin appear
• Dry skin interferes with sleep or daily activities
• You notice sudden, unexplained changes in skin condition
• Symptoms suggest an underlying medical condition