Effect of borage oil consumption on fatty acid metabolism, transepidermal water loss and skin parameters in elderly people

Human skin is not able to biosynthesize gamma-linolenic acid (GLA, 18:3 omega 6) from the precursor linoleic acid (LA), or arachidonic acid (AA) from dihomo-gamma-linolenic acid (DHGLA). Dietary supplementation with GLA-rich seed oil of borage skips the step of hepatic 6-desaturation of fatty acids (FA) and, therefore, compensates the lack of these essential FA in conditions with impaired activity of delta 6-desaturase. Twenty-nine healthy elderly people (mean age 68.6 years), received a daily dose of 360 or 720 mg GLA for 2 months, using Borage oil in gelatine capsules (Quintesal(R)180, manufacturer Galderma Laboratorium GmbH, Freiburg, Germany). The effects of fatty acids derived from ingested borage oil capsules on skin barrier function were assessed by measurement of transepidermal water loss (TEWL). The consumption of borage oil induced a statistically significant improvement of cutaneous barrier function in the elderly people, as reflected in a mean decrease of 10.8% in the transepidermal water loss. Thirty-four percent of the people noted itch before borage oil consumption and 0% afterwards. Dry skin was claimed to be reduced from 42 to 14%, but no significant alteration of skin hydration was measured. The FA-composition of erythrocyte membrane phospholipids demonstrated an increase of GLA (+70%) and DHGLA (+18%) and a reduction of saturated and monounsaturated FA. There was no significant alteration in nervonic acid or in AA content, but an increase in the DHGLA/AA ratio (+23%). Thus, the consumption of borage oil by elderly people lead to alteration of FA metabolism and improved skin function. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.