Vegetable Oil - Female Phytotherapy & Cosmetics

Evening Primrose Oil

The evening primrose: GLA, female cycle, PMS, and menopause

Latin name

Oenothera biennis L.

Family

Onagraceae

History & Botany

Evening primrose is a biennial plant native to North America, where Native American peoples used all its parts. Introduced to Europe in the 17th century as an ornamental plant, its large sulfur-yellow flowers bloom in the late afternoon (hence its English name, Evening Primrose), and close in the morning, offering their nectar only to nocturnal butterflies and hawk moths.

The real revolution came in the 1970s-1980s, when British researchers discovered the exceptional richness of its seeds in gamma-linolenic acid (GLA). Evening primrose oil became, within a few years, one of the best-selling dietary supplements in the world, particularly in the United Kingdom, where it received medicinal authorization for atopic eczema and mastodynia.

Morphology

Large biennial plant, 50 to 150 cm tall, upright and robust. Large bright yellow flowers with 4 petals, solitary or in terminal clusters, opening in the late afternoon. Elongated capsules containing numerous small brown seeds. The entire plant emits a slight lemon scent when crushed.

Oil extraction

Extraction by cold first pressing of mature seeds, without solvents. Low yield (15 to 20%), making it an expensive oil. Pale golden yellow color, light, with a fine and subtle odor. Mandatory refrigeration, away from light and air.

Oenothera biennis L.

Large bright yellow flowers blooming in the late afternoon

Fatty Acid Composition & Biochemistry

Organoleptic Properties

Appearance

Virgin oil

A fluid, clear oil, light, non-greasy to the touch. Rapid skin penetration. Slightly viscous when cold, more fluid at room temperature.

Color

Fresh virgin oil

Pale golden yellow to light yellow. A color that is too dark (brown-orange) or cloudy indicates advanced oxidation or insufficient quality.

Odor

Fresh oil

Fine and subtle, slightly vegetal and lemony. A rancid or strong fishy odor indicates oxidation: the oil should not be consumed.

Taste

Oil in solution / capsule

Mild and slightly vegetal, without marked bitterness. Very slightly fatty and lemony note. Neutral taste in gastro-resistant capsules.

Storage

Oxidative stability

A fragile oil sensitive to oxidation (dominant PUFAs). Mandatory refrigeration, away from light. Adding vitamin E is recommended for stabilization. Shelf life: 6 to 12 months once opened.

Medicinal Properties & Use in Women

PMS & Mastodynia

Best-documented indication. Clinically proven to reduce cyclic mastodynia (painful and tense breasts before menstruation). Alleviates irritability, water retention, bloating, and premenstrual migraines. Optimal results after 2 to 3 cycles of continuous treatment.

Menopause & Vaginal Dryness

GLA reduces the intensity and frequency of hot flashes. Improves vaginal dryness through oral intake and topical application. Supports the trophicity of genital mucous membranes during postmenopausal atrophy, complementary to phytoestrogens.

Eczema & Atopic Skin

Former medicinal indication in the United Kingdom. Reduces itching, redness, and dryness in atopic eczema. Restores the deficient skin barrier in ceramides. Used in topical application and orally, with a synergistic effect between the two routes of administration.

Endometriosis & Pelvic Inflammation

GLA, a precursor of anti-inflammatory PGE1, helps reduce chronic pelvic inflammation in endometriosis. Alleviates severe menstrual pain and reduces pro-inflammatory prostaglandins PGE2 responsible for uterine cramps.