Nces, Universitdegli two. Materials and Techniques Studi di Milano, San Paolo Hospital, Milan, Italy. We initially searched the PubMed archiveThis01 March 2021 with theat the Department of Wellness Sciences,surface disease” OR on overview was performed keywords and phrases “vitamin” AND “ocular Universitdegli “dry eye Milano, San Paolo Hospital, Milan, Italy.4230 initially searched the PubMed Studi di disease”. We inspected the results of We papers and identified 254 papers, archive on 01 March 2021 with the keywords and phrases “vitamin” AND “ocular efficacy; (two) clinical delivering the following useful facts: (1) Preclinical evidence of surface disease” OR “dry of efficacy. Two evaluators independently inspected the complete text 254 references evidence eye disease”. We inspected the results of 4230 papers and identified andpapers, giving the following valuable facts: reports with duplicated outcomes, case series with to retrieve relevant papers. Excluded were (1) preclinical evidence of efficacy; (2) clinical evidence of efficacy. Two with no abstract or papers not written full text and references ten patients or much less, papersevaluators independently inspected the in English. No restrictions to the presence of papers. Excluded have been reports with duplicated results, case series on retrieve relevant a control group or length of follow-up were applied. In the finish, 55 with 10 sufferers or much less, papers with no abstract or papers not written in English. No studies were analyzed within this evaluation. 3. Resultsrestrictions on the presence of a handle group or length of follow-up had been applied. Within the end, 55 research had been analyzed within this review.3. Benefits 3.1. Vitamin A 3.1. Vitamin A 3.1.1. Preclinical EvidenceThere is massive preclinical evidence supporting the advantageous effects of vitamin A adThere is big systemically or topically) around the ocular surface. The mechanisms ministration (eitherpreclinical evidence supporting the effective effects of vitamin A of administration (either systemically or topically) on the ocular surface. The mechanisms of action of vitamin A around the OS are reported in Figure 1. Vitamin A increases cIAP-2 web conjunctival action of vitamin A around the OS are reported in Figure 1. Vitamin A increases conjunctival mucin expression and promotes appropriate corneal and conjunctival wound healing, reducmucin expression and promotes correct corneal and conjunctival wound healing, reducing ing keratinization. These effects happen to be shown by quite a few research different animalaniusing various keratinization. These effects have been shown by various studies making use of mal models of DED: vitamin A promotes wound healing [4] by enhancing epithelialepimodels of DED: vitamin A promotes wound healing [4] by directly directly enhancing thelial [5,6], and reducingreducing cell apoptosis [7] and corneal keratinization [8].are repair repair [5,6], and cell apoptosis [7] and corneal keratinization [8]. These effects These effects are by an increase inincrease in tear volumequalityand On a rabbit On a rabbit model mediated mediated by an tear volume [9,10] and [9,10] [5]. good quality [5]. model of OSD, of OSD, on account of antiglaucoma treatment options, topical was as productive as topical cyclosporine cydue to antiglaucoma remedies, topical vitamin A vitamin A was as efficient as topical closporine in decreasing OS inflammation, as evaluated by AMPK Storage & Stability impression cytology [11]. in minimizing OS inflammation, as evaluated by impression cytology [11].3.1.1. Preclinical EvidenceFigure 1. Effects of vitamin A suppleme.