Natural (Mineral, Vegetable, Coconut, Essential) Oils and Contact Dermatitis

Abstract

Natural oils include mineral oil with emollient, occlusive, and humectant properties and the plant-derived essential, coconut, and other vegetable oils, composed of triglycerides that microbiota lipases hydrolyze into glycerin, a potent humectant, and fatty acids (FAs) with varying physico-chemical properties. Unsaturated FAs have high linoleic acid used for synthesis of ceramide-I linoleate, a barrier lipid, but more pro-inflammatory omega-6:-3 ratios above 10:1, and their double bonds form less occlusive palisades. VCO FAs have a low linoleic acid content but shorter and saturated FAs that form a more compact palisade, more anti-inflammatory omega-6:-3 ratio of 2:1, close to 7:1 of olive oil, which disrupts the skin barrier, otherwise useful as a penetration enhancer. Updates on the stratum corneum illustrate how this review on the contrasting actions of NOs provide information on which to avoid and which to select for barrier repair and to lower inflammation in contact dermatitis genesis.

Evaluation of moisturizing and irritation potential of sacha inchi oil

“…Ingredients with emollient, humectant, and/or skin protection functions are commonly included in moisturizers. Several natural oils have been reported as efficient moisturizing agents through their emollient and occlusive properties . For example, olive oil, one of the most commonly used moisturizing products, has been reported to provide moisturizing, anti‐bacterial, anti‐inflammatory, and UV protection activities .…”

“…Several natural oils have been reported as efficient moisturizing agents through their emollient and occlusive properties. 4,5 For example, olive oil, one of the most commonly used moisturizing products, has been reported to provide moisturizing, anti-bacterial, anti-inflammatory, and UV protection activities. [6][7][8] These activities are associated with the presence of fatty acids, including omega-3 (α-linolenic acid, 0.5%-0.9%), omega-6 (linoleic acid, 2%-10%), and nonessential omega-9 (oleic acid, up to 78%-80%) fatty acids, squalene and phenolics.…”

Anti-aging Effects of Select Botanicals: Scientific Evidence and Current Trends

“…Coconut oil can moisturize dry aging skin [10,35]. Sixty-two percent of the fatty acids in VCO are of similar length and 92% are saturated, which allows for tighter packing that results in a greater occlusive effect than olive oil [10]. The triglycerides in coconut oil are broken down by lipases in normal skin flora to glycerin and fatty acids [10].…”

“…Sixty-two percent of the fatty acids in VCO are of similar length and 92% are saturated, which allows for tighter packing that results in a greater occlusive effect than olive oil [10]. The triglycerides in coconut oil are broken down by lipases in normal skin flora to glycerin and fatty acids [10]. Glycerin is a potent humectant, which attracts water to the corneal layer of the epidermis from the outside environment and the deeper skin layers [10].…”

“…In addition to the decreased quantity and quality of collagen fibers, aging skin loses proper barrier function. The normal human skin barrier is composed of keratin-filled keratinocytes embedded in an extracellular matrix consisting predominately of saturated long chain lipids: cholesterol, ceramide fatty acids, and free fatty acids [10]. Together these provide a strong, flexible, water-tight barrier, which becomes altered as the skin ages.…”