How Humectants Keep Your Skin Moisturized

To start, let's bust a moisturizer myth — the main role of a moisturizer is not adding moisture to the skin, but trapping it. A good moisturizer contains humectants and emollients that lock water in the outer layer of the skin, giving any damaged cells a chance to repair. The difference between the two — humectants are water-loving ingredients, whereas emollients are a type of lipid or oil (think beeswax, coconut oil, olive oil), that help seal the moisture in and lubricate the skin. Together, they make extremely effective moisturizers for all skin types, including oily and acne-prone.

How Humectants Work

Two ways — the outside environment and deeper layer of your skin. In humid environments, humectants work as magnets, literally drawing moisture in from the air. If it’s arid, however, they need the help of occlusive ingredients. As for your skin, humectants can pull water from the deeper layer of the skin (the dermis) and draw it to the top layer (the epidermis), locking it in. This increases the level of moisture in the outermost shell of the epidermis (the stratum corneum).

Types of Humectants

There are over 800 types of humectants—from natural to synthetic. Skincare manufacturers like synthetic humectants because they cost less than natural ones, but they can end up doing more harm than good. In fact, synthetic humectants can leave the skin dehydrated on a long-term basis. This is because when certain humectants, like propylene glycol, draw moisture out from the inner layers of the dermis, they don’t actively work to replenish that moisture and can leave your skin dehydrated if that water is not replaced. 

Common synthetic humectants include:

• Butylene glycol
• Dicyanamide
• Sodium PCA
• Sodium lactate
• Sorbitol
• Tremella Extract
• Urea

Of the natural humectants, many are in the body already, and are classified as “Natural Hydrating Factors” (NHF, for short). These include things like amino acids, lactic acids, glucosamin, peptides, urea, sugars, and kreatin—to name a few.  

Common natural humectants include:

Aloe Vera

This is one of the most effective naturally hydrating ingredients available. It penetrates skin deeply and quickly, hydrating at the surface and at the lower levels.

Alpha Hydroxy Acid

These are naturally derived from plants and are mostly used in anti-aging formulations. Some common AHAs include glycolic acid, malic acid, lactic acid, and mandelic acid. AHAs exfoliate your skin, clearing the dead skin cells, so the moisturizers can seep deeper into your skin layers.

Glycerin

Glycerin holds water really well and it works by finding an equilibrium between the water content in the air and in the skin. Along with the benefits of deep hydration, the texture of glycerin makes it perfect for skin care because it glides on smoothly and evenly.

Honey

Honey is loaded with useful amino acids, minerals, enzymes, and vitamins that keep your skin healthy and smooth. It also has a natural ability to hold onto water (the perfect humectant), hydrating without creating an oily feel. 

Hyaluronic Acid

A natural molecule present throughout the body, Hyaluronic Acid helps hydrate and cushion joints, eyeballs, and skin. It has a natural ability to hold onto water, and is able to adjust according to humidity levels, helping your skin cope with even dry climates.

Lactic Acid

Lactic acid is an alpha-hydroxy acid that has both humectant and exfoliating properties. Joshua Zeichner, MD, Mount Sinai Hospital director of cosmetic and clinical research, explains, “At low concentrations, lactic acid acts as a humectant, helping to pull in hydration to the outer skin layer. At higher concentrations, it helps dissolve connections between skin cells on the surface of the skin to enhance exfoliation.” 

 Words by: Holly Brown