Glossary

Medical glossary

Many words from product packages and the doctor's office sound complicated, even though they stand for simple things. The glossary collects terms used in this reference, with short explanations and no unnecessary detail.

When you understand what's written on the package and what the doctor said, it's easier to ask a follow-up question and harder to fall for a pretty promise.

— Editor's note

Skin structure

Skin: The body's largest organ. It separates the body from the outside world, helps hold in moisture and heat, and plays a part in the sense of touch.
Epidermis: The outer layer of the skin. Its cells are constantly renewed: new ones form deep down and gradually rise to the surface.
Stratum corneum: The topmost part of the epidermis, made of hardened, flattened cells. Together with oily substances, it helps the skin keep from losing water.
Dermis: The layer under the epidermis. It contains blood vessels, nerve endings, hair follicles and glands, and its fibers give the skin strength and elasticity.
Sebaceous glands: Glands that produce sebum, the skin's natural oil. It softens skin and hair; in the teen years these glands are often more active.
Melanin: The pigment that determines the color of skin, hair and eyes. It partly absorbs ultraviolet but doesn't provide full protection.

Sun

Ultraviolet radiation: The invisible part of sunlight. Too much ultraviolet causes burns and over time damages the skin and eyes.
UV index: A measure of the strength of the sun's ultraviolet used by WHO. At a value of 3 and above, protection is needed; at 8 and above, extra protection.
Sunburn: Skin damage from ultraviolet: redness, stinging, soreness, sometimes blisters. An extensive burn with feeling unwell overall needs a doctor.
Tan: Darkening of the skin after sun exposure due to melanin production. It's a reaction to ultraviolet already received, not reliable protection from it.
Sunscreen: A skin product that reduces the effect of ultraviolet. It only works if applied and reapplied as the directions say.

Care

Cleansing: Removing sweat, dust and leftover products from the skin. Gentle cleansing doesn't leave the skin feeling tight.
Exfoliation: Removing the top layer of dead skin cells, either mechanically or with special formulas. Not everyone needs it, and not often.
Moisturizing: Care that helps the skin hold on to water. Usually this means applying a moisturizer after washing.
Skin barrier: A general name for the ability of the upper layers of skin to hold in moisture and keep out irritants. Hot water and rough rubbing weaken it.
Patch test: Applying a small amount of a new product to a limited area of skin to notice irritation before using it more widely.
Ingredient list: The list of a product's components printed on the package. It helps you avoid substances you've already reacted to.

Doctors and research

Dermatologist: A doctor who specializes in skin, hair and nails: examines them, makes a diagnosis and prescribes treatment.
Primary care doctor: A general practice doctor you can see with any complaint. If needed, they will refer you to the right specialist.
Clinical study: Testing a method of care, treatment or diagnosis on a group of people according to a plan described in advance, following safety rules.
Control group: Study participants who don't receive the product being tested. Comparing with them shows whether the product has any benefit.
Placebo: A substance with no active ingredient that looks just like the one being tested. It helps separate a real effect from expectations.
Systematic review: A piece of research that gathers and compares all available studies on a single question according to strict rules.

Where these words appear in the reference

Topics
Topics in four groups: sun and light, water and cold, care and ingredients, skin changes. Plus the article catalogue.
Prevention
Caring for your skin every day: the UV index forecast, shade, gentle cleansing, moisturizing and sleep.
Methods
Sun protection, cleansing and moisturizing, calmly keeping an eye on your skin, and photos for comparison.
Research
Where knowledge about skin comes from, how to read the promises on a package, and why skin care myths persist.
Questions
Questions about sun, dryness, irritation and moles that are worth discussing with a dermatologist or primary care doctor.
Gentle scrubs (in Russian)
A note at an archived address: why exfoliate, when it's better to hold off, and how not to harm your skin.

Methods
Sun protection, cleansing and moisturizing, calmly keeping an eye on your skin, and photos for comparison.
Topics
Topics in four groups: sun and light, water and cold, care and ingredients, skin changes. Plus the article catalogue.
Research
Where knowledge about skin comes from, how to read the promises on a package, and why skin care myths persist.
Sources
What this reference is based on, how we select information, and where the limits of our texts lie.

Sources

General dermatologist recommendations on skin care
WHO — Global Solar UV Index: A Practical Guide

This page reflects generally accepted views on skin care as of the date it was prepared. If your skin behaves unusually or something worries you, make decisions together with a dermatologist, not based on the text of this reference.