GLA (Gamma-Linolenic Acid)

Anti-inflammatorySkinPMS

An omega-6 that actually reduces inflammation. The exception to the 'reduce omega-6' rule — used for PMS, eczema, dry eye, and joint inflammation.

EvidenceModerate

Strong for dry eye and atopic dermatitis (eczema). Moderate for cyclical breast tenderness in PMS, rheumatoid arthritis joint pain, diabetic neuropathy. Older PMS evidence was strong but newer trials more mixed. Effects: 6–12 weeks.

Most omega-6 fatty acids are pro-inflammatory (linoleic acid from seed oils), but GLA is a notable exception. The body converts it to dihomo-gamma-linolenic acid (DGLA), which generates anti-inflammatory prostaglandins. It's the active compound in evening primrose oil, borage oil, and black currant seed oil — used for decades for PMS (especially breast tenderness), eczema, dry eye, and inflammatory arthritis. Best evidence is in dry eye and atopic dermatitis. Conversion to DGLA requires adequate B6, magnesium, and zinc — deficiencies in those nutrients blunt GLA's effects.

Form
Borage oil (highest GLA concentration ~20–24%) — most dose-efficient. Evening primrose oil (8–10% GLA) — better-studied historically. Black currant seed oil (15–17% GLA + some omega-3 ALA).
Dose
300–600 mg GLA daily. Borage oil: 1,000–2,000 mg of oil delivers the target dose. Evening primrose: 3,000–6,000 mg of oil.
Timing
With food. Anytime.
Schedule
Daily.
Side effects
Generally well-tolerated. Mild GI upset, soft stool, headache. Borage oil contains pyrrolizidine alkaloids in raw form — use only PA-free certified products.
Interactions
Anticoagulants and antiplatelets — mild additive blood-thinning. Anti-seizure medications (phenothiazines especially) — theoretical seizure-threshold lowering.
Contraindications
Seizure disorders (relative — evening primrose has been associated with rare seizures). Pregnancy (limited safety data above food intake). Pre-surgery (stop 7–14 days before).
Lab markers
Not standard. Functional: dry eye symptoms, eczema scoring, joint pain.
Food sources
GLA isn't found in significant amounts in everyday food — only in specific seeds (borage, evening primrose, black currant, hemp). Hemp seeds are the most accessible food source.

Pairs with

Omega-3 fish oil (balances the omega-6 load and provides complementary anti-inflammatory action). Vitamin B6, magnesium, zinc (cofactors for GLA → DGLA conversion). Vitamin E (protects the unsaturated oil from oxidation).