Seborrheic dermatitis is a common complaint brought to pediatricians. Also known as “cradle cap” in infants and “dandruff” in adolescents, the condition is believed to be triggered by Malassezia yeasts.1 The natural course correlates androgen-driven excess sebum production: spontaneous improvement by age 1 year and reoccurrence with puberty. Treatment of this condition has supported a billion dollar market for over-the-counter treatments,2 loosely regulated by a Food and Drug Administration monograph.
The Internet provides easy access to several websites that give directions for home treatments. A popular approach is application of oil (olive, vegetable, or mineral), left on for as short as 15 minutes or as long as overnight, followed by brushing to loosen scales, and finally shampooing.3-6
While oil application may be risk free, a potential concern arises when considering a possible Malassezia virulence factor regulated by its metabolic lipid pathways. In vivo, Malassezia digests sebum into saturated and unsaturated fatty acids.1 Only the saturated molecules are essential while the unsaturated fatty acids are a by-product.1 Organic oils (such as olive oil) contain both saturated and unsaturated lipids and may be counterproductive to treat a condition whose etiology is linked to Malassezia. In fact, olive oil is a standard in vitro culture media for Malassezia.7 Saturated fatty acids likely encourage Malassezia overgrowth and excess unsaturated fatty acids may induce inflammation and scaling. As nondigestible oil, mineral oil may provide a triglyceride-free alternative to organic oils.
Based on the evidence currently available, it may be prudent to avoid organic oils, especially olive oil, when treating seborrheic dermatitis or other inflammatory skin diseases triggered by colonizing microflora.
Correspondence: Dr Glenn, 600 William St, Ste 328, Oakland, CA 94602 (eglenn@slu.edu).
Published Online: August 13, 2012. doi:10.1001 /archpediatrics.2012.765
Author Contributions:Study concept and design: Siegfried. Acquisition of data: Siegfried and Glenn. Analysis and interpretation of data: Siegfried and Glenn. Drafting of the manuscript: Siegfried and Glenn. Critical revision of the manuscript for important intellectual content: Siegfried. Study supervision: Siegfried.
Financial Disclosure: None reported.
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