Borage Seed Oil: What It Contains and What Research Shows
Borage seed oil is a liquid extracted from the seeds of the borage plant, and it contains a fatty acid called gamma-linolenic acid (GLA) that your body does not make on its own. Most borage seed oil supplements contain between 17% and 25% GLA by weight, though this varies by brand and processing method. The oil also holds linoleic acid and other compounds that may influence how your immune system responds to stress and inflammation.
Research on borage seed oil has focused mainly on joint health and inflammatory response rather than immune function directly. Several studies have looked at whether GLA affects how the body handles inflammatory markers, with mixed but generally positive findings in people with joint discomfort. The evidence for immune support specifically is thinner—most claims rest on the idea that GLA influences immune cell behavior, but human studies measuring actual immune outcomes are limited.
What matters for your decision: borage seed oil is not a treatment for any condition, and no amount of it will prevent illness on its own. It is a source of a fatty acid your diet may lack, and some people add it to their routine hoping it supports their body's baseline inflammatory response. Whether that translates to feeling better or staying healthier depends on your individual situation and what else you are doing.
Key Takeaways
- Borage seed oil contains GLA, a fatty acid that may influence inflammatory response, but evidence for direct immune support in humans is limited.
- Most supplements contain 17% to 25% GLA; the dose in studies showing any effect ranges from 1,400 to 2,800 mg daily, taken for weeks or months.
- Borage seed oil can thin blood and interact with blood thinners, NSAIDs, and some diabetes medications, so check with your doctor before starting if you take any of these.
- Digestive upset, headache, and mild nausea are the most common side effects, usually appearing in the first week and often fading as your body adjusts.
How Much to Take and What Form Works Best
Borage seed oil comes as a liquid (bottled oil you measure by the teaspoon) or in soft gel capsules. Capsules are easier to dose consistently and have less taste, but they cost more per serving. Liquid oil is cheaper and lets you adjust the amount, though it tastes bitter and can be hard to swallow straight.
The dose used in most research studies ranges from 1,400 to 2,800 mg of borage seed oil daily, usually split into two or three doses taken with food. A typical soft gel capsule holds 1,000 to 1,500 mg, so you would take one to three per day depending on the brand and your goal. If you are using liquid oil, one teaspoon is roughly 5 ml or about 5,000 mg, so a quarter to half teaspoon daily would fall in the research range.
Start with the lower end of the dose range—around 1,400 mg daily—and stay there for at least four weeks before deciding whether it is working for you. Taking more does not speed results; your body needs time to incorporate GLA into cell membranes and adjust its inflammatory response. If you tolerate it well and want to increase, move up gradually over a week or two.
Choosing a Borage Seed Oil Product
Look for products that list the GLA content per serving on the label—it should be stated in milligrams, not just as a percentage. Reputable brands test their oils for purity and list the results on their website or provide them on request. Third-party testing by organizations like NSF International or USP is a good sign, though not all quality products carry it.
Borage seed oil oxidizes (breaks down) when exposed to light and heat, so buy bottles that are dark or opaque and store them in a cool, dark place or in the refrigerator after opening. Liquid oil lasts about six months once opened; capsules last longer because they are sealed. Check the expiration date before buying, and do not use oil that smells rancid or off.
Price varies widely—capsules typically cost $0.15 to $0.40 per 1,000 mg serving, while liquid oil runs $0.05 to $0.15 per serving. Cheaper is not always worse, but extremely low prices sometimes signal lower GLA content or older stock. Buy from retailers with good return policies so you can send it back if it arrives damaged or if you do not tolerate it.
Side Effects and Who Should Avoid It
The most common side effects are mild: digestive upset, headache, nausea, and loose stools, usually appearing in the first few days and fading within a week as your body adjusts. Taking it with food reduces stomach irritation. If side effects persist beyond a week or worsen, stop and wait a few days before trying again at a lower dose.
Borage seed oil has a mild blood-thinning effect and can interact with blood thinners like warfarin or apixaban, NSAIDs like ibuprofen taken regularly, and some diabetes medications. If you take any of these, talk to your doctor or pharmacist before starting borage seed oil—you may need monitoring or a dose adjustment. Pregnant and nursing people should avoid it because safety data is limited.
People with a history of bleeding disorders or those scheduled for surgery should mention borage seed oil to their healthcare provider at least two weeks before the procedure. Stop taking it one to two weeks before surgery to reduce bleeding risk. If you have a shellfish allergy, check the product label—some borage oils are derived from fish oil or processed in shared facilities.
How Long It Takes to Notice Any Effect
If borage seed oil is going to make a difference for you, you will not notice it in days. Most research studies ran for 8 to 12 weeks before measuring changes, and some took 24 weeks. Your body needs time to incorporate GLA into cell membranes and for any shift in inflammatory response to show up as something you can feel.
Give it at least four to six weeks at a consistent dose before deciding whether it is worth continuing. Keep a straightforward log of how you feel—energy, joint comfort, digestion, sleep—so you have a baseline to compare against. If you see no change after eight weeks, it may not be the right tool for you, and stopping is fine.
If you do notice improvement, keep taking it consistently. The benefit usually depends on staying on it; stopping for a week or two often means the effect fades. This is not a supplement you take for a month and then stop—it is something you either add to your routine long-term or do not use at all.
Borage Seed Oil Versus Other Omega Fatty Acid Sources
Borage seed oil is one way to get GLA, but it is not the only one. Fish oil and flaxseed oil contain different omega fatty acids (EPA, DHA, and ALA) that your body can convert to GLA, though the conversion is inefficient. Evening primrose oil also contains GLA and is sometimes used the same way borage oil is, though borage seed oil typically has a higher GLA concentration per dose.
If you already take fish oil or flax regularly and tolerate it well, adding borage seed oil on top is possible but not necessary—you are already getting omega fatty acids, just different ones. If you are starting from scratch and want to explore GLA specifically, borage seed oil is a more direct source than trying to convert other oils. If you are vegetarian or vegan, borage seed oil is a better choice than fish oil.
The choice often comes down to what your body tolerates and what fits your budget. Borage seed oil is not cheaper than fish oil, and it is not a replacement for eating fatty fish or seeds if you can. It is an option if you want to experiment with GLA specifically and you do not have contraindications with blood thinners or upcoming surgery.
Storing and Using Borage Seed Oil Long-Term
Once you open a bottle of borage seed oil, oxidation starts. Liquid oil in a dark bottle lasts about six months in the refrigerator; capsules last longer because they are sealed. Write the opening date on the label so you know when to replace it. Rancid oil tastes noticeably bad and may cause digestive upset, so if it smells off, throw it out.
If you travel, capsules are easier to pack than liquid oil. Keep them in a cool bag or insulated case if you will be in heat for more than a few hours. Liquid oil can leak, so use a sealed container or stick with capsules when traveling.
If you stop taking borage seed oil for any reason, you do not need to taper it—you can stop anytime. If you want to restart after a break, begin at the lower dose again rather than jumping back to your previous amount, since your tolerance may have reset.
Frequently Asked Questions
Can I take borage seed oil every day long-term?
Yes, many people take it daily for months or years without problems. The longest studies ran for 24 weeks with no serious safety issues. If you tolerate it well and want to continue, daily use is generally considered safe, though you should check in with your doctor annually if you take blood thinners or other medications that might interact.
Will borage seed oil help me avoid getting sick?
There is no evidence that borage seed oil prevents colds, flu, or other infections. It may influence how your body handles inflammatory response, but that is not the same as preventing illness. It is one small piece of a much larger picture that includes sleep, movement, diet, and handwashing.
What is the difference between borage seed oil and evening primrose oil?
Both contain GLA, but borage seed oil typically has 17% to 25% GLA per dose, while evening primrose oil has about 8% to 10%. This means you need a smaller amount of borage seed oil to get the same GLA dose. Evening primrose oil is sometimes easier to find and may be cheaper, but you will take more capsules to match the dose.
Can I take borage seed oil with my multivitamin?
Yes, borage seed oil and multivitamins do not interact. Take them together with food to reduce any stomach upset. If your multivitamin also contains omega fatty acids or GLA, you are not doubling up on anything harmful, but you may be getting more GLA than you intended—check the labels to know your total dose.
Does borage seed oil taste bad?
Liquid borage seed oil tastes bitter and slightly grassy. Most people find it unpleasant straight, so mixing it into yogurt, applesauce, or a smoothie helps. Capsules have no taste, which is why many people prefer them despite the higher cost.