title: Effect of olive and sunflower seed oil on the adult skin barrier: implications for neonatal skin care.
abstract: Natural oils are advocated and used throughout the world as part of neonatal skin care, but there is an absence of evidence to support this practice. The goal of the current study was to ascertain the effect of olive oil and sunflower seed oil on the biophysical properties of the skin. Nineteen adult volunteers with and without a history of atopic dermatitis were recruited into two randomized forearm-controlled mechanistic studies. The first cohort applied six drops of olive oil to one forearm twice daily for 5 weeks. The second cohort applied six drops of olive oil to one forearm and six drops of sunflower seed oil to the other twice daily for 4 weeks. The effect of the treatments was evaluated by determining stratum corneum integrity and cohesion, intercorneocyte cohesion, moisturization, skin-surface pH, and erythema. Topical application of olive oil for 4 weeks caused a significant reduction in stratum corneum integrity and induced mild erythema in volunteers with and without a history of atopic dermatitis. Sunflower seed oil preserved stratum corneum integrity, did not cause erythema, and improved hydration in the same volunteers. In contrast to sunflower seed oil, topical treatment with olive oil significantly damages the skin barrier, and therefore has the potential to promote the development of, and exacerbate existing, atopic dermatitis. The use of olive oil for the treatment of dry skin and infant massage should therefore be discouraged. These findings challenge the unfounded belief that all natural oils are beneficial for the skin and highlight the need for further research.
authors.affiliation: Academic Unit of Dermatology Research, Department of Infection and Immunity, Faculty of Medicine, Dentistry and Health, University of Sheffield Medical School, Sheffield, UK. s.danby@sheffield.ac.uk
authors.forename: Simon G
authors.initials: SG
authors.lastname: Danby
authors.forename: Tareq
authors.initials: T
authors.lastname: AlEnezi
authors.forename: Amani
authors.initials: A
authors.lastname: Sultan
authors.forename: Tina
authors.initials: T
authors.lastname: Lavender
authors.forename: John
authors.initials: J
authors.lastname: Chittock
authors.forename: Kirsty
authors.initials: K
authors.lastname: Brown
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Cork
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D000069463:Olive Oil; D010938:Plant Oils / Q000008:administration & dosage*; D012016:Reference Values; D016037:Single-Blind Method; D012867:Skin / Q000187:drug effects*; D012869:Skin Absorption / Q000187:drug effects* / Q000502:physiology; D017592:Skin Care / Q000379:methods; D000074242:Sunflower Oil
chemical_list: D000069463:Olive Oil; D010938:Plant Oils; D000074242:Sunflower Oil