Skin care products form the largest sector of all cosmetics and personal care products, with moisturizers taking the highest market share. Skin care technology has come a long way since the first cold creams, with the introduction of new raw materials and advancements in emulsion technology, products with good functionality and consumer appeal have been developed to drastically improve the quality of our skin.
Our fascination with beauty has deep history, with products having been found at ancient burial sites in Egypt, Greece, and Rome. Even the bible mentions lotions made of oils and spices.And similar to alcohol, moisturizers have been developed according to the materials available in their region: popular ingredients throughout time have included avocado, palm, and olive oils, to name a few.
The first significant advancement of simple moisturizers occurred around 1840 when emulsifiers were developed to create stable emulsions (mixtures of two or more liquids which normally don’t homogenize when added together) and Pond’s first skin cream came onto the market. Today there are thousands of different types of moisturizers available for various skin conditions.
At their core, moisturizers are designed to maintain the skin’s integrity and barrier functions, including:
Improving skin quality
Maintaining moisture content
Alleviating symptoms of dry skin
Since the majority of these products are marketed to maintain or restore youthful appearance without initiating changes in skin function or structure, they are considered cosmetics in the US.
However, certain products may contain active ingredients marketed to treat conditions such as wrinkles or acne, and these are considered drugs, and regulated as such by the FDA. You can read more about drugs vs cosmetic determination on the FDA’s website.
Did you know? While many products may be marketed as “Cosmeceuticals” that is simply a marketing term, and has no legal meaning.
Moisturizers are typically sold for the hands, body, face, and eye area.
While they typically do not differ significantly in their ingredients, they may have different amounts or “actives” to address particular concerns. These products are marketed differently mostly due to the hydration differences of the skin on different parts of the body, and their sensitivity. For example, hands may be washed multiple times per day, while the face is acne prone. This is just one example why we might want to select different moisturizers for these different applications.
Cleansers vary in their ability to remove epidermal surface lipids (sebum) and depending on the strength of the cleanser, where it is applied, and the skin type, they may be too effective in cleaning the skin resulting in exposing the Stratum Corneum (SC: outermost protective layer) to potential damage. But cleansers are just one piece of the puzzle, environmental factors such as humidity, sun, and pollution, along with diet, medications, water consumption, and medicines all can take a toll on our skin. Applying
moisturizers helps to restore our skin’s barrier function which gets compromised through daily life.
Moisturizer is actually a generic term used to describe the ingredients which add moisture to the skin, which are typically composed of the following:
Humectants: Substances which bind and attract water, they work by increasing the water content in the top layer of the skin by enhancing water absorption from the dermis to the epidermis and even
pulling in atmospheric moisture. These ingredients can actually dry out the dermis layer of the skin in very dry environments, or if the barrier function of the skin is compromised. Humectants are often combined with Occlusives to help prevent water loss in this manner. Examples of Humectants include Glycerin and Hyaluranic Acid.
Occlusives: Large, heavy molecules which provide a physical barrier to the outer layer of skin, helping prevent Transepidermal Water Loss (TEWL). Occlusives tend to be sticky or greasy, which is why they are effective at reducing water evaporation from the skin. Petrolatum is a popular Occlusive, as are Evening Primrose and Jojoba oils.
Emollients: Improve the appearance of the skin by smoothing and filling in the gaps of dry, flaky skin cells.
Emollients can also protect and lubricate the skin, and may function as both Occlusives and Humectants. Mineral oil, Cocoa & Shea Butters are some examples of Emollients.
This is one of the better videos on understanding how these ingredients work
Moisturizing is just one component of a healthy skin regimen, along with (at a minimum) Cleansing to remove dirt and excess sebum, and Exfoliation to remove old, loose skin cells to prepare the skin for moisture.
Moisturizers are typically applied after cleansing. With the skin still wet, it’s the perfect opportunity to capture some of that moisture by locking it in with a moisturizer.
Moisturizers have different textures, absorption rates, oil & water content, emollient properties, and varying irritant potential based on the ingredients used, which is why there are so many to choose from. Based on the individual differences in skin type and sensitivity, selecting the right moisturizer for your skin is fairy subjective.
Oily skin may benefit from more water-based formulations, so they don’t deposit too much oil onto the skin.
Dry skin benefits from extra oil, to help seal in moisture.
Various aesthetic properties are important to cosmetics, and there is a balance between clinical performance and consumer perception. While aesthetics may vary from person to person, there are sensoral properties by which moisturizers may be evaluated to help bring a somewhat objective rubric to a subjective determination:
Rub-Out Ease with which a product absorbs upon application
Appearance Physical appearance, gloss, shine, thickness
Pick-Up Product texture when rubbed
Slip How the product glides on the skin
After-Feel Smoothness & softness after application
Delayed After-Feel How does the skin feel after a certain amount of time after applying the product