Skin Care Categories

Two categories of products join each other under thevast umbrella of so-called cosmetics: makeup and skin care products. While makeup includes products

such as lipsticks, foundation, mascara, eye shadow, and blush, skin care products include lotions and creams, sunscreens, facial serums, massage or tanning oils, baby skin care products, facial masks, scrubs, hand sanitizers, and many others.

Although lotions and creams are the most prevalent forms of skin care products,

there are many other less ubiquitous formulations such as solutions, suspensions,gels, oils, ointments, balms, and even powders.

Lotions and Creams

Lotions and creams are emulsions formed by dispersion of an oil phase into an

aqueous phase or an aqueous phase into an oil phase. The emulsion is then called

an oil-in-water or water-in-oil emulsion, respectively. Generally speaking, most

lotions are oil-in-water because they are more pleasant to the touch and do not

leave a greasy residue. Because of the immiscibility of the two phases, oil

droplets are dispersed and stabilized within the continuous aqueous phase with

the aid of an emulsifier, which can also act as a surfactant—as in, for example,

lecithin and cetearyl alcohol. Sometimes a thickener, such as gum or starch, is

also used to bring more stability to the emulsion by increasing the viscosity of

the continuous phase and reducing the risk of separation of the two phases.

Lotions, which are thinner than creams, are usually reserved for body formulations since they are easier to spread.

Solutions

Solutions are liquid formulations made of soluble solids dissolved in an aqueous

phase and, perhaps, other water-miscible liquids, such as rubbing alcohol.

Because of their high water content, and if they do not contain enough rubbing

alcohol, solutions may need preservatives.

Suspensions

Suspensions are made of insoluble solid particles that remain suspended within

the continuous phase. Although some settling might occur, the suspension can be recovered by shaking the container prior to application. Caking is a more serious issue, because it is more difficult to reverse than settling.

Examples of suspensions include bead or clay-based exfoliators.

Gels

Gels are semisolid solutions or suspensions in which the water phase is

thickened and transformed into a homogenous gel. Gels are more stable than liquid suspensions because settling is less likely to occur. Gelling agents include gums and cellulose derivatives. Gels are refreshing and have a pleasant cosmetic feel due to the high water content, without greasy residue.

Examples of gels include hand sanitizers.

Oils

Oils are very simple to make because they are a mixture of miscible components

and so, unlike solutions, do not require preservation. The absence of water

makes oily preparations less favorable for bacterial growth. As for the oxidation

that might occur within the oils, unsaturated fatty acids, it can be slowed down by adding antioxidants such as vitamin E and by storing the final preparation in an amber bottle, away from light and heat, which may act as oxidation

catalyzers. Therapeutic active oils or fragrant essential oils are often diluted with neutral or carrier oils to bring their concentration to adequate levels.

Oils are mainly preferred for dry skin as facial serums, for hair care, and for body massages.

Ointments

Ointments are highly viscous formulations made mostly of thick bases such as

lanolin, with oils and oil-miscible ingredients. There is little to no water content in ointments. They are very greasy and have poor cosmetic appeal.

Ointments are much more common in the pharmaceutical field, examples

including corticosteroids and antibiotic ointments.

Balms

Balms are solidified ointments; they include a high proportion of waxes and

butters, which solidify at room temperature. Balms are very easy to make and require no preservatives. They are favored when an occlusive effect is needed, such as when skin is severely damaged by aggressive weather.

Examples include lip and heel balms.

Powders

Cosmetic powders are fine, solid powders that can be offered loose or compacted, often blended with coloring pigments and possibly other agents to improve fluidity, prevent caking, or bring some benefits to the skin.

Examples include mineral and baby powder.

Ice Cubes, Steam Baths, and Warm Compresses

Ice cubes, steam baths, and warm compresses are considered concoctions rather than real skin care preparations and are often used for various skin ailments.

There is a common belief that applying cold (ice cubes or refrigerated moisturizers) to the skin helps firm and tighten it. Such “tightening” of the skin

is temporary, however, and cold will constrict the blood vessels and thus

decrease immediate absorption of the applied “nutrients.”

Steam baths are a common practice to open pores and facilitate skin cleaning

and blackhead removal. Steam can be generated by hot water with or without

additives. This practice is not recommended for people with certain medical conditions, including asthma, COPD, and cardiovascular disease, or for pregnant women.

Cold or warm compresses and poultices are often applied to swollen areas

such as puffy eyelids. It is important that the temperature of the compress

respects the skin’s tolerance. People with rosacea or dilated blood vessels should

check with their dermatologist before using compresses or poultices.