Evaluation of moisturizing and irritation potential of sacha inchi oil

J Cosmet Dermatol. 2020 Apr;19(4):915-924. doi: 10.1111/jocd.13099. Epub 2019 Aug 23.


Objective: The moisturizing and irritation effects of sacha inchi oil were evaluated.

Study design: The moisturizing effect on the skin was clinically assessed using a regression study design. Sacha inchi oil or olive oil (benchmark) was applied on the left or right lower leg of the subjects for 14 days followed by application discontinuation for 2 days. The TEWL, skin moisture content and dryness appearance were observed.

Methods: The fatty acid composition and characteristics of cold-pressed sacha inchi seed oil were determined. Skin tissues cultured ex vivo were used to assess primary irritation induced by the oil by examining keratin 1 expression and TNF-α and IL-1α release from the oil-applied tissues.

Results: The sacha inchi oil contained 42.3% linolenic acid and 39.5% linoleic acid. This oil's saponification, iodine, acid and peroxide values were 168.58 ± 1.55 mg KOH/g, 203.00 ± 0.04 g I2 /100 g, 1.68 ± 0.03 mg KOH/g, and 1.95 ± 0.26 mEq peroxide/kg, respectively. Compared with nontreated skin tissues, induced secretion of TNF-α and IL-1α and disruption of keratin 1 integrity in the stratum corneum layer were not found in the sacha inchi oil-treated tissues. In a clinical study with 13 volunteers, the improvement in moisture content and skin dryness appearance at the sacha inchi oil-applied site was comparable with that observed at the olive oil-applied site.

Conclusions: The sacha inchi oil was mild to the skin and benefited dry skin.

Keywords: irritation; moisturizing effect; olive oil; sacha inchi oil.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Biopsy
  • Cosmeceuticals / administration & dosage*
  • Cosmeceuticals / adverse effects
  • Cosmeceuticals / chemistry
  • Elasticity / drug effects
  • Epidermis / drug effects*
  • Epidermis / metabolism
  • Epidermis / pathology
  • Euphorbiaceae / chemistry*
  • Female
  • Healthy Volunteers
  • Humans
  • Interleukin-1alpha / metabolism
  • Linoleic Acid / analysis
  • Middle Aged
  • Plant Oils / administration & dosage*
  • Plant Oils / adverse effects
  • Plant Oils / chemistry
  • Seeds / chemistry*
  • Skin Irritancy Tests
  • Treatment Outcome
  • Tumor Necrosis Factor-alpha / metabolism
  • Water Loss, Insensible / drug effects
  • Young Adult
  • alpha-Linolenic Acid / analysis


  • Cosmeceuticals
  • IL1A protein, human
  • Interleukin-1alpha
  • Plant Oils
  • TNF protein, human
  • Tumor Necrosis Factor-alpha
  • alpha-Linolenic Acid
  • Linoleic Acid