Types Of Moisturizers Moisturizing Types:
 1.Moisturizers: Moisturizers of the new millennium include agents that mimic natural ingredients and function as botanicals, including vitamins, hydroxy acids, and retinoids. Other common ingredients are collagen, elastin, DNA, ribonucleic acid (RNA), lecithin, sodium hyaluronate, sodium passive cutaneous anaphylaxis (PCA), and ceramides. A simple explanation of a moisturizer's mechanism states that water, which otherwise would have been lost, is held by hygroscopic properties in the stratum corneum. Subsequently, this contributes to the smoothing of the skin surface due to swelling of the outer layers. Moisturizers impart a temporary barrier to damaged stratum corneum, which allows time for reparation of this layer.
2.Humectants: Humectants are substances that attract water when applied to the skin. The source of the water is transepidermal, unless the relative humidity is very high (>80%). Humectants can also increase transepidermal water loss. At times, this can lead to a perception of skin tightness or dryness. Examples of humectants include glycerin, sorbitol, urea, alpha hydroxy acids (AHAs), and sugars. Lactic acid, particularly the salt form ammonium lactate, has demonstrated an ability to reduce the thickened stratum corneum of xerosis as well as to remove and clear the thick scales in ichthyosis and other hyperkeratotic conditions.
 3.Occlusion: Lanolin was the first substance to be used in an occlusive system. Its use as a barrier has been known for thousands of years. Similar to other moisturizers, lanolin functionality was thought to be occlusive; therefore, lanolin prevents the loss of water. Today, other functions of lanolin are known as well. It has the reputation of being a contact sensitizer; however, this is controversial. Because of this reputation, petrolatum is now the principal ingredient used in occlusive formulations. Depending on the concentration, petrolatum physically blocks the surface of the stratum corneum and reduces transepidermal water loss. This increases the water content in the stratum corneum, thus producing a state of hydration. Two reasons exist as to why occlusion is one of the best treatments of dry skin. First, transepidermal water is the most effective source of water (water added to the skin evaporates in 10-20 min). Second, these occlusive agents have an emollient effect.
4.Natural moisturizing factor: NMF is a combination of several low molecular weight substances. These substances include amino acids, pyrrolidone carboxylic acid, lactate, urea, ammonia, uric acid, glucosamine, creatinine, citrate, sodium, potassium, calcium, magnesium, phosphate, chlorine, sugar, organic acids, peptides, and other unidentified substances. Many of these substances are added to moisturizers to help its hygroscopic properties. Too much of these substances cause irritation. For example, lactic acid and propylene glycol also act as exfoliants, and urea leads to dehiscence of corneocytes and contains broad-spectrum antibacterial properties. Thus, maintenance and hydration of the stratum corneum is the result of a multifaceted masterpiece.
 5.Emollients: Emollients fill the spaces between the corneocytes, thus providing therapeutic improvement to defects in desquamation. Emollients function in smoothing the roughened skin, changing the skin's appearance, lubricating, replacing natural skin lipids, and providing occlusion. Emollients are composed of water in oil emulsions; thus, oil is the largest component, which ranges from 3-25%. The concentration of oil in emollients is important for easier spreading and for the degree of occlusion that is desired. Emollients with low spreading value are most often used for night and facial creams, around eye wrinkles, and in cosmetics. They include castor oil, almond oil, and oleyl oleate. Emollients with medium spreading value are most often used in day and sun protection creams and oils. They include octyl dodecanol, hexyl decanol, oleyl alcohol, and decyl oleate. Emollients with high spreading value are most often used in body lotions, hand creams and lotions, and bath additives. They include isopropyl stearate, isopropyl palmitate, isopropyl myristate, hexyl laureate, and dioctyl cyclohexane. The type of emollient and the water-to-oil ratio determines the classification of the moisturizer, which is important for different types of skin. Individuals with oily skin should choose an oil-free moisturizer. Two types of oil-free moisturizers are available. One group contains strictly oil-free products, such as propylene glycol and glycerin, which are drying and can cause stinging on irritated skin. The second group contains emollient esters, which have an oil-like behavior. Esters have been shown by the Rabbit Ear Assay to be possible comedogenics. Esters marketed for dry skin contain heavier oils (eg, petrolatum), and normal skin products usually contain mineral oil and propylene glycol as the main ingredients. Types Of Moisturizers:
All moisturizers fall, basically into 2 main types: Oil-in-water emulsions and water-in-oil emulsions.
 1.Oil-in-water Emulsions: The oil-in-water moisturizers sometimes also contain substances called humectants which attract water from the surroundings, but this may have its own disadvantage because humectants may sometimes absorb too much water from the skin itself thereby increasing its dryness. A commonly used humectant is glycerine. Newer ingredients have been added to increase the efficacy of this group of moisturizers, but still their effect remains temporary.
2.Water-in-oil Emulsions: The second category of moisturizers comprise the newer water-in-oil emulsions. They are marketed generally as creams or lotions. Being oil-based products, these trap moisture in the skin by forming ab occlusive film on the skin surface; this forms a barrier retarding water loss. Many of these products are also called anti-dehydrating creams. Tips On Choosing A Moisturizers  |
