A moisturizer, or emollient, [1] is a cosmetic preparation used for protecting, moisturizing, and lubricating the skin. These functions are normally performed by sebum produced by healthy skin. [2] The word "emollient" is derived from the Latin verb mollire, to soften. [3]
In the human body, water constantly evaporates from the deeper layers of the skin through an effect known as transepidermal water loss. By regulating its water content, human skin naturally maintains a dry, easily shed surface as a barrier against pathogens, dirt, or damage, while protecting itself from drying out and becoming brittle and rigid. The ability to retain moisture depends on the lipid bilayer between the dead skin cells. [4]
Moisturizers modify the rate of water loss, with active ingredients of moisturizers falling into one of two categories: occlusives and humectants. [5]
Occlusives form a hydrophobic coating on the surface of the skin, keeping moisture from escaping. The more occlusive the formulation, the greater the effect. Ointments are more occlusive than aqueous creams, which are more occlusive than lotion. [5] Water loss through the skin is normally about 4–8 g/(m2⋅h). A layer of petrolatum applied to normal skin can reduce that loss by 50–75% for several hours. [4] Oils naturally produced by the human body moisturize through this same mechanism. [2]
Humectants are hydrophilic and absorb water. They absorb water from humid air (when >70% humidity) to moisturize the skin. More commonly, however, they draw out water from the dermis into the epidermis, making deeper skin dryer. [6] When used in practical applications, humectants are combined with occlusives. [7] Moisturizers commonly contain water, which acts as a temporary hydration agent. [8]
There are many different types of moisturizers. Petrolatum is one of the most effective moisturizers, although it can be unpopular due to its oily consistency. [9] [10]
Other popular moisturizers are cetyl alcohol, cetearyl alcohol, cocoa butter, isopropyl myristate, isopropyl palmitate, lanolin, liquid paraffin, polyethylene glycols, shea butter, silicone oils, stearic acid, stearyl alcohol and castor oil, and other oils.
Moisturizers may also be available as lotions, creams, ointments, bath oils, or soap substitutes.
Mineral oils and waxes are not prone to oxidation or rancidity. [11] For this reason, they have essentially replaced vegetable oils in emollients and topical medication.
Moisturizer cosmetics may additionally contain antioxidants, ceramides, emulsifiers, fragrances, penetration enhancers, preservatives, and solvents. Some products are marketed as having anti-wrinkle and skin enhancement effects. Many plant and animal extracts have been claimed to impart skin benefits, but such claims are presented with little scientific evidence.
Moisturizers are used for the treatment of certain skin diseases, such as psoriasis, ichthyosis vulgaris, xerosis, and pruritus in atopic dermatitis. More often, they are bases or vehicles for topical medication, such as in Whitfield's ointment. They are often combined with humectants, such as salicylic acid and urea. [12]
Moisturizers are also widely used in sunscreens, antiperspirants, skin cleansers, shaving creams, aftershaves, and hair tonics.
Moisturizers are used in disposable diapers to prevent dry skin and diaper dermatitis.
A Cochrane review noted that moisturizers show some beneficial effects in eczema. [13] The same review did not find evidence that any one moisturizer was better than another. [13] Furthermore, because none of the different types of moisturizers are more effective than the others, consumers need to choose one or more products according to their age, affected body site, climate/season, and personal preference. [14]
Moisturizers can improve skin comfort and may reduce disease flares such as related to atopic dermatitis. [15] They can be used as leave-on treatments, bath additives, or soap substitutes. There are many different moisturizer products, but the majority of leave-on treatments (from least to most greasy) are one of the following: lotions, creams, gels, or ointments.
Persistent moisturization to the skin via water contact may contribute to an allergic reaction or contact dermatitis.[ citation needed ] This could allow foreign objects to penetrate the skin.[ ambiguous ]
Changes in the skin's normal ecological environment–either atop or within the skin–can also allow for the overgrowth of pathogens. [8]
Aromas or food additives in moisturizers may trigger an immune reaction, including development of an allergy. [16] [17]
There is currently no regulation over use of the term "hypoallergenic". In fact, some pediatric skin products marketed as hypoallergenic contained allergens. [18] [19]
Those with eczema are especially vulnerable to allergic reaction with lotions and creams, as their compromised skin barrier allows preservatives to bind with and activate immune cells. [20]
The American Academy of Allergy, Asthma, and Immunology released a warning in 2014 that natural lotion containing ingredients commonly found in food (such as goats milk, cow's milk, coconut milk, or oil) may introduce new allergies, potentially causing an allergic reaction upon later consuming such foods. [16] A paper published in 2021 noted that frequent skin moisturization in early life might promote the development of food allergy, even when skin conditions such as eczema are taken into account. [17]
Paraffin-based skincare products and contaminated clothing can pose a serious fire hazard. [21] Between 2010 and 2018, paraffin was linked to 50 fire incidents (49 of which were fatal) in the U.K. [22] A West Yorkshire Fire and Rescue Service study found that clothing contaminated with cream containing only 21% paraffin, when set alight, was fully engulfed in flame in 3 seconds. [21] The Medicines and Healthcare products Regulatory Agency (MHRA) released a warning in 2008 about the flammability of paraffin-based products. [23] MHRA recommends that regular paraffin users change their sheets regularly, refrain from smoking and/or bringing open flames near paraffin-coated people or objects. [24] MHRA also recommends that skin creams containing any paraffin have a flammability warning on the packaging. [25]
Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to covering the entire body. Dermatitis is often called eczema, and the difference between those terms is not standardized.
Lanolin, also called wool fat, wool yolk, wool wax, sheep grease, or wool grease, is a wax secreted by the sebaceous glands of wool-bearing animals. Lanolin used by humans comes from domestic sheep breeds that are raised specifically for their wool. Historically, many pharmacopoeias have referred to lanolin as wool fat ; however, as lanolin lacks glycerides, it is not a true fat. Lanolin primarily consists of sterol esters instead. Lanolin's waterproofing property aids sheep in shedding water from their coats. Certain breeds of sheep produce large amounts of lanolin.
A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes including creams, foams, gels, lotions, and ointments. Many topical medications are epicutaneous, meaning that they are applied directly to the skin. Topical medications may also be inhalational, such as asthma medications, or applied to the surface of tissues other than the skin, such as eye drops applied to the conjunctiva, or ear drops placed in the ear, or medications applied to the surface of a tooth. The word topical derives from Greek τοπικόςtopikos, "of a place".
Nummular dermatitis is one of the many forms of dermatitis. It is characterized by round or oval-shaped itchy lesions. The name comes from the Latin word "nummus," which means "coin."
Desonide (INN) is a low-potency topical corticosteroid anti-inflammatory that has been available since the 1970s. It is primarily used to treat atopic dermatitis (eczema), seborrheic dermatitis, contact dermatitis and psoriasis in both adults and children. It has a fairly good safety profile and is available as a cream, ointment, lotion, and as a foam under the tradename Verdeso Foam. Other trade names for creams, lotions, and ointments include Tridesilon, DesOwen, Desonate. It is a group VI corticosteroid under US classification, the second least potent group.
Baby oil is, in general terms, an inert oil for the purpose of keeping skin soft and supple. It is often used on babies for the purpose of maintaining "baby-soft" skin, but it is also often used by adults for skincare and massage.
Atopic dermatitis (AD), also known as atopic eczema, is a long-term type of inflammation of the skin (dermatitis). It results in itchy, red, swollen, and cracked skin. Clear fluid may come from the affected areas, which can thicken over time. AD may also simply be called eczema, a term that generally refers to a larger group of skin conditions.
Natural skin care uses topical creams and lotions made of ingredients available in nature. Much of the recent literature reviews plant-derived ingredients, which may include herbs, roots, flowers and essential oils, but natural substances in skin care products include animal-derived products such as beeswax, and minerals. These substances may be combined with various carrier agents, preservatives, surfactants, humectants and emulsifiers.
In chemistry and materials science, a conditioner is a substance or process that improves the quality of a given material. Conditioning agents used in skincare products are also known as moisturizers, and usually are composed of various oils and lubricants. One method of their use is as a coating of the substrate to alter the feel and appearance. For cosmetic products, this effect is a temporary one but can help to protect skin and hair from further damage.
Panthenol (also called pantothenol) is the alcohol analog of pantothenic acid (vitamin B5), and is thus a provitamin of B5. In organisms, it is quickly oxidized to pantothenic acid. It is a viscous transparent liquid at room temperature. Panthenol is used in pharmaceutical and cosmetic products as a moisturizer and to improve wound healing.
Xeroderma, xerosis or xerosis cutis, or simply dry skin, is a skin condition characterized by excessively dry skin.
Lotion is a low-viscosity topical preparation intended for application to the skin. By contrast, creams and gels have higher viscosity, typically due to lower water content. Lotions are applied to external skin with bare hands, a brush, a clean cloth, or cotton wool.
Skin care or skincare is a range of practices that support skin integrity, enhance its appearance, and relieve skin conditions. They can include nutrition, avoidance of excessive sun exposure, and appropriate use of emollients. Practices that enhance appearance include the use of cosmetics, botulinum, exfoliation, fillers, laser resurfacing, microdermabrasion, peels, retinol therapy, and ultrasonic skin treatment. Skin care is a routine daily procedure in many settings, such as skin that is either too dry or too moist, and prevention of dermatitis and prevention of skin injuries.
Amcinonide is a topical glucocorticoid used to treat itching, redness and swelling associated with several dermatologic conditions such as atopic dermatitis and allergic contact dermatitis. Amcinonide can also be classified as a multi-functional small molecule corticosteroid, which has been approved by the FDA and is currently marketed as an ointment, lotion, or cream. It acts as both a transcription factor for responses to glucocorticoids and modulator for other transcription factors while also regulating phospholipase A2 activity.
Vaseline is an American brand of petroleum jelly-based products owned by transnational company Unilever. Products include plain petroleum jelly and a selection of skin creams, soaps, lotions, cleansers, and deodorants.
Topical steroids are the topical forms of corticosteroids. Topical steroids are the most commonly prescribed topical medications for the treatment of rash and eczema. Topical steroids have anti-inflammatory properties and are classified based on their skin vasoconstrictive abilities. There are numerous topical steroid products. All the preparations in each class have the same anti-inflammatory properties but essentially differ in base and price.
A barrier cream is a topical formulation used in industrial applications and as a cosmetic to place a physical barrier between the skin and contaminants that may irritate the skin. There are many other terms for creams designed to protect skin from harmful substances, including skin protective creams, pre-work creams, antisolvent gels, protective ointments, and shielding lotions. Three classes of barrier creams are used: water repellent creams, water-soluble creams, and creams designed for special applications. Barrier creams may contain substances such as zinc oxide, talc or kaolin to layer over the skin. For hand care they are designed to protect against the harm from detergents and other irritants.
Aquaphor is a brand of over-the-counter (OTC) skin care ointments manufactured by Beiersdorf Inc., an affiliate of Beiersdorf AG. Aquaphor is offered in four product ranges: There are two skin protectant ointments. Aquaphor Original Ointment, used as a compounding agent and Aquaphor Advanced Therapy Healing Ointment, sold in mass retail outlets. The other product ranges include: Aquaphor Lip Repair and Lip Repair + Protect SPF 30, and Aquaphor Baby.
Dermatoses induced by Personal Protective Equipment are skin lesions that occur due to the use of personal protective equipment (PPE). Personal Protective Equipment such as masks, face shields, goggles, gloves and gowns can cause abrasion in the skin and retain moisture in body parts, particularly the face. During the COVID-19 pandemic, healthcare workers and general public need to use personal protective equipment, sometimes for extended duration, which may result in skin problems due to friction, pressure, long-term sealing and moisture retention.
Topical glucocorticoids are the topical forms of glucocorticoids. Topical glucocorticoids are used in the treatment of many skin conditions. They provide anti-inflammatory, antimitotic, and immune-system suppressing actions through various mechanisms.
