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The knowledge of skin biology enables the identification of active ingredients which are essential for healthy skin and crucial for the maintenance of its barrier function and integrality. Polysaccharides are known with their protective effects on the skin; therefore, the development of cosmetic formulations with these ingredients can enhance the efficacy of the formulations [168].

In cosmetics, applications of polysaccharides range from peelings with candy sugar crystals up to cleansing products. Polysaccharides used in cosmetics can be categorized as functional and active polysaccharides. Functional polysaccharides can be used in the formulation technology such as gelling agent, film former, thickener, conditioner, suspending agent, and emulsifier while active polysaccharides are used in the cosmetics because of their ability in forming hydrogel structure with moisturizing effect [169]. In the gelling masks, that are spread on the skin in liquid form and then removed after they have solidified into a rubbery substance, the main ingredient is alginic acid. Agar, a mixture of agarose and agaropectin, is used as a consistency and bonding agent. Food-grade carrageenan is an entirely safe and appropriate ingredient for toothpaste, like furcelleran. Chitosan is used for hair conditioning purposes in shampoos and hair gels and used in toothpaste and mouthwashes as a bacteria-inhibiting component. It can also be used in skincare products as a cationic filming agent. Glucan has skin-protecting and tightening features and it is used for the skincare after peeling and laser treatments, after shaving as well as an additive for body lotions. Carboxymethyl cellulose, which is also called sodium cellulose glycolate, is obtained by chemical modification of cellulose. It forms water-soluble sodium salts with thickening properties and the salts can be used in cleansing and washing products as highly effective carriers for dirt particles. Dextrins can retain perfumes and can be used for the slow release of the perfume [168, 170]. Hyaluronic acid is also widely used in cosmetic practice. As an injectable dermal filler, it is preferred by most anti-aging, esthetic and plastic specialists. For instance, hyaluronic acid is used for skin regeneration, wrinkle-treatment, and wound healing as an effective, non-invasive, non-surgical alternative due to its enormous ability to bind water and easiness of implantation [67]. Similar to hyaluronic acid, xanthan has gentle skin-smoothing properties and moisturizing characteristics [170].

The data obtained from clinical studies have been shown that polysaccharide-based formulations prevent transepidermal water loss and protect the skin barrier function. Thus, natural polysaccharides are suitable to be used in cosmetic formulations effective in skin protection and maintenance of structural integrity of the skin. Besides, natural polysaccharides can interact with other ingredients in a formulation, such as active substances, surfactants, and salts. The only drawback of many of these natural polymers is that their composition may vary depending on their geographical origin and the manufacturing process that can result in differences in chemical purity and quality which can lead to skin reactions [168]. Therefore, careful analysis of the chemical properties of polysaccharides and their by-products are extremely important for cosmetic production.