Gamma-Linolenic Acid (GLA)

What is Gamma-Linolenic Acid (GLA)?

Gamma-linolenic acid (GLA) is an omega-6 polyunsaturated fatty acid that sits at a key branch point in the body's fat metabolism pathway. Unlike most omega-6 fats, GLA acts more like omega-3s in the body — it converts into compounds that actively calm inflammation rather than promote it. It's found naturally in the seed oils of evening primrose, borage, and black currant plants.

How does Gamma-Linolenic Acid (GLA) work?

Once absorbed, GLA is converted in the body to dihomo-gamma-linolenic acid (DGLA), which then produces prostaglandin E1 — a powerful compound that helps reduce inflammation, support healthy skin barriers, and ease hormonal symptoms. This pathway is distinct from the more common omega-6 route that can fuel inflammation, making GLA's anti-inflammatory effects somewhat unique among omega-6 fatty acids.

What forms does Gamma-Linolenic Acid (GLA) come in?

Most people get GLA through evening primrose oil capsules because they are widely available and well-studied, though borage oil delivers more GLA per capsule and may require fewer pills to reach therapeutic doses. Black currant seed oil also provides a balanced mix of omega-3 and omega-6 fatty acids alongside GLA. Liquid oils exist but are less convenient for consistent dosing.

Where it comes from:

Evening primrose, the most common GLA source, has been used by Indigenous North American peoples for centuries as a food and medicinal plant. Scientific interest in GLA as a therapeutic compound picked up strongly in the 1970s–1980s when British researchers began studying its role in eczema, PMS, and inflammatory disease. Borage has a long history in European herbal medicine, and black currant seed oil has been used in traditional Northern European wellness practices.

What does Gamma-Linolenic Acid (GLA) help with?

• Eczema and dry, itchy skin: People with eczema often have a reduced ability to convert dietary fats into GLA, leaving their skin barrier weakened and prone to dryness and irritation. Supplementing GLA directly helps restore healthier skin fat composition, improving moisture retention and reducing redness and itch over time. Results typically take 3–4 months of consistent use to become noticeable.
• PMS and breast tenderness: GLA from evening primrose oil has been used widely for cyclic breast pain (mastalgia) and general PMS discomfort, with the idea that it helps normalize the hormonal signaling that makes breast tissue oversensitive. Clinical evidence is mixed overall, but evening primrose oil is one of the most studied natural options for this use and is often better tolerated than conventional treatments.
• Rheumatoid arthritis pain and stiffness: GLA's ability to shift the body toward less inflammatory fat compounds makes it a reasonable support tool for people with rheumatoid arthritis. Studies using borage oil and evening primrose oil at meaningful doses have shown reductions in joint tenderness and morning stiffness, though GLA works best as a complement to, not a replacement for, standard care.
• Diabetic nerve pain (neuropathy): Diabetes can impair the body's ability to process essential fats, and research has looked at GLA supplementation as a way to support nerve health in people with diabetic peripheral neuropathy. Several trials have found improvements in nerve conduction and reduced pain symptoms, particularly with evening primrose oil over 6–12 months.
• Inflammation and inflammatory conditions: GLA's conversion to DGLA and prostaglandin E1 places it in a genuinely anti-inflammatory role that differs from most omega-6 fats. This makes it potentially useful across a range of chronic low-grade inflammatory conditions, particularly when used alongside omega-3 fatty acids for a more complete anti-inflammatory fatty acid profile.
• Menopausal skin changes: Some research has looked at GLA for the skin dryness and thinning that accompany menopause, with evidence suggesting that evening primrose oil may help maintain skin hydration and elasticity. It's often paired with vitamin E or omega-3s for broader skin support during this transition.
• ADHD (children, adjunctive support): A handful of trials have examined omega-6 and omega-3 fatty acid combinations including GLA in children with ADHD, finding modest improvements in attention and hyperactivity. GLA is not a standalone treatment for ADHD but may offer some support as part of a broader nutritional approach.
• High blood pressure (mild support): GLA has shown mild blood pressure-lowering effects in some studies, likely through prostaglandin E1's ability to relax blood vessels. The effect is modest and should not be relied on as primary treatment, but may contribute meaningfully in a comprehensive heart-health plan.
• Bone health (combined with omega-3s): Some older research found that a combination of GLA and EPA (an omega-3) improved bone density in older women with osteoporosis. The combination appears to work better than either alone, and the mechanism may involve enhanced calcium absorption and reduced bone breakdown signals.

What can Gamma-Linolenic Acid (GLA) help prevent?

• Progression of diabetic neuropathy (with early supplementation and good blood sugar management)
• Skin barrier deterioration in people with compromised essential fatty acid metabolism

Which foods are rich in Gamma-Linolenic Acid (GLA)?

1. Evening primrose oil: Contains 8–10% GLA and is the most widely studied dietary/supplement source of this fatty acid.
2. Borage oil: The richest natural source of GLA at 20–24% concentration, delivering more GLA per gram than any other common oil.
3. Black currant seed oil: Contains 15–19% GLA and also provides some omega-3 alpha-linolenic acid, offering a more balanced fatty acid profile.
4. Hemp seeds and hemp seed oil: Contains a modest but meaningful amount of GLA (around 2–3%) alongside a favorable omega-6 to omega-3 ratio.
5. Spirulina: One of the few non-seed food sources of GLA, though in smaller amounts; also provides protein and other anti-inflammatory compounds.

Practical Tips:

GLA is not meaningfully present in common everyday foods like vegetables, grains, or animal products. Your body can theoretically make small amounts of GLA from linoleic acid (found in sunflower, safflower, and corn oils), but this conversion is often inefficient, especially with age, high sugar intake, stress, or certain health conditions. To support GLA's anti-inflammatory effects through diet more broadly, focus on reducing refined seed oils high in plain linoleic acid (which competes with GLA's pathway), increasing omega-3 rich foods like fatty fish and walnuts, and eating a whole-foods diet that limits processed fats.

What are the side effects of Gamma-Linolenic Acid (GLA)?

• Mild nausea or stomach upset, especially on an empty stomach
• Loose stools or soft bowel movements at higher doses
• Headache (reported occasionally, particularly with evening primrose oil)
• Mild bloating or gas
• Skin breakouts (rare, usually at very high doses)
• Increased bleeding time at very high doses: relevant before surgery

Good to know:

GLA is considered safe for most adults at standard supplemental doses. Side effects are usually mild and often improve after the first week or two of use.

How much Gamma-Linolenic Acid (GLA) should you take?

• Recommended daily: Eczema and skin: 320–480 mg GLA/day (from EPO or borage oil). PMS and breast pain: 240–320 mg GLA/day. Rheumatoid arthritis: 1,400–2,800 mg GLA/day (borage oil studies used these higher amounts). Diabetic neuropathy: 480 mg GLA/day (from EPO). Note: always check the GLA content on the label, not just the total oil amount.
• Best time of day: No strong preference; splitting doses morning and evening with meals is a practical approach that may improve absorption and reduce stomach upset.
• With or without food: Always take with food — GLA is a fat-soluble nutrient and absorbs significantly better when consumed with a meal that contains some fat.
• Time to effect: Skin conditions: 3–4 months. PMS and breast pain: 2–3 menstrual cycles. Joint symptoms: 6–12 weeks at therapeutic doses. Nerve support: 6–12 months.
• How long to take it: GLA is typically used continuously for the duration of the condition being addressed. Long-term daily use is considered safe; clinical trials have run for up to 2 years without safety concerns. No mandatory cycling needed, though reassessing need every 3–6 months is sensible.