Many people confuse emollients and moisturizers, and the ingredients in both products can be confusing. Many people do not know which type of emollient or moisturizer is best for their skin, and using the wrong moisturizing product can cause problems such as clogged pores and acne, or even allergic reactions.
Emollients are used to soften the skin, especially hard and scaly skin associated with eczema, and to form a protective occlusive barrier on cracked or fragile skin to aid in its healing. Moisturizers, on the other hand, are creams, lotions, or ointments that deliver water to the skin or help to retain moisture within the skin. Nowadays, the two terms are often used interchangeably.
There are many emollients and moisturizers available for sale in general stores and pharmacies, including oils, lotions, creams, and ointments.
The uses of emollients and moisturizers include soothing dry skin, masking fine lines and wrinkles, treating contact dermatitis/eczema, and as a base for makeup.
Emollients and moisturizers contain occlusive and humectant ingredients. They typically contain other ingredients such as surfactants, fragrances, and preservatives.
Occlusives are non-human sourced oils, usually mixed with water and emulsifiers to form lotions or creams. They provide a layer of oil on the surface of the skin to reduce water loss from the stratum corneum. The strongest occlusive is an oily ointment, which includes pure oil formulations such as white soft paraffin or petroleum jelly. However, if used on the face, it may cause acne or be too greasy. Face creams have a moderate strength and can be used on hands and feet or on dry skin on the face. Lotions are easier to absorb and leave a less greasy feeling, making them more suitable for use in areas with more hair or on the face, where the skin is less dry. Some people also like to add a layer of oil to their body during a shower to ensure an even distribution.
Sorbolene and glycerin cream are common moisturizers that are non-greasy, inexpensive, and available over the counter without a prescription.
Humectants are a type of hydrophilic compound that absorbs moisture from the humid air to increase the water-holding capacity of the stratum corneum, which results in a moisturizing effect on the skin. Humectants act like magnets to capture moisture from the atmosphere, which is why the air feels less humid in winter, when the skin is drier. Common humectants include glycerin, urea, and hyaluronic acid.
Glycerol
Urea
Alpha-hydroxy acids, such as lactic acid or glycolic acid.
Moisturizers on the market typically contain humectants and occlusives, which increase their moisturizing effect. In addition to humectants and occlusives, some products also contain preservatives to keep the formulation stable and extend its shelf life.
Preservatives
Creams and lotions are prone to microbial contamination, and preservatives are added to extend their shelf life. The preservatives in moisturizers can cause allergic contact dermatitis in sensitive individuals.
Other ingredients
Manufacturers often add other ingredients to distinguish their products from competitors and attract consumers. However, the efficacy of some ingredients that claim to reduce signs of aging may not be supported by scientific evidence, as large molecules such as peptides and collagen cannot penetrate the stratum corneum to achieve their claimed effects.
Adverse reactions to moisturizers
Irritation
People with sensitive skin related to atopic dermatitis or rosacea often experience irritation from moisturizers and other skincare products, such as burning or stinging. If the irritation is mild and transient, the product may still be used. However, if contact dermatitis develops, the product should be discontinued.
Allergic contact dermatitis
Allergic contact dermatitis to moisturizers is rare. However, contact allergy to preservatives, fragrances, or emulsifiers can be tested using patch testing.
Folliculitis
Occlusive moisturizers can cause or exacerbate acne, perioral dermatitis, folliculitis, and bacterial pyoderma.
Thermal burns
Wax-containing ointments on clothing or bedding can cause burns. Exposure to open flames or cigarettes can also result in thermal burns.
When purchasing moisturizers, it is essential to understand one’s skin type and pay attention to the ingredients to choose the most suitable product. If in doubt, consult with a dermatologist.