What is borage seed oil?

Borage seed oil is a nutritional supplement which is rich in essential fatty acids that can regulate the body’s immune system and fight joint inflammation. The available evidence suggests that borage seed oil may improve the symptoms of rheumatoid arthritis.

Family: Herbal medicine of the Boraginaceae family
Scientific name: Borago officinalis
Other names: Star flower oil, bee bread, tailwort, common bugloss, echiun amoenum

Borage seed oil is made from the seeds of the borage plants. Borage is an annual herb native to the Mediterranean region but grown in other countries, including the UK. You can buy it over the counter from pharmacies and health food shops in the form of capsules or bottled oil.

How does it work?

Borage seed oil contains very high levels of two types of polyunsaturated omega-6 essential fatty acids, 20–26% gamma-linolenic acid (GLA) and linolenic acid (LA, which your body converts to GLA).

GLA is an essential fatty acid that’s important for maintaining a joint’s cell structure and function. Your body converts it into hormone-like substances called prostaglandins, which regulate your immune system and fight joint inflammation. GLA might also suppress inflammatory responses by directly acting on some inflammatory cells.

Several factors can interfere with your body’s production of GLA from LA, including:

  • ageing
  • dietary deficiencies
  • viral infections
  • some diseases.

Other oils generally used in normal diet (like sunflower oil) only contain LA. Borage seed oil is the richest source of pure GLA. It also contains tannic, oleic and palmetic acid.

Side-effects

Reported side-effects of borage seed oil include:

  • nausea
  • indigestion
  • headaches
  • rashes.

It also contains small amounts of some liver toxins, but you can get preparations that are free of these toxins.

No studies to assess the safety of borage seed oil in people with arthritis and related conditions appear to have been done, but studies on other GLA-rich oils suggest that they’re relatively safe with no serious side-effects.

The effects borage seed oil has on drugs haven’t been well studied, but you should be cautious if you take anti-inflammatory drugs (for example cortisone) and anticoagulants because interactions are possible. Some sedatives and medications for hypertension can dampen down borage seed oil’s anti-inflammatory properties.

No trials have been done to find out the best dosage for arthritis-related conditions. Early studies have found that high doses of GLA (more than 1 g a day) are needed to partly ease symptoms.

Trials for rheumatoid arthritis

Two RCTs evaluated the effect of borage seed oil in treating rheumatoid arthritis. All participants were asked to continue with their usual treatment plan during the trial period. The number of participants withdrawing from the studies, due to treatment ineffectiveness or side-effects, was small. Reported side-effects were minor and included belching, diarrhoea and flatulence.

Trial 1

In the first trial, 37 people with rheumatoid arthritis were randomly assigned to receive either borage seed oil containing 1.4 g GLA or a placebo of cotton seed oil daily for 24 weeks.

Compared to the placebo group, who showed no improvement during the trial, participants who received borage seed oil showed an improvement in:

  • joint tenderness
  • number of swollen joints
  • morning stiffness.

Trial 2

In the second RCT, 56 participants with rheumatoid arthritis were randomly assigned to take either a daily dose of borage seed capsules containing 2.8 g GLA or placebo capsules of sunflower seed oil for six months.

  • 64% of those on borage seed oil showed improvement in joint tenderness and morning stiffness, compared to only 21% of those on placebo treatment.
  • There was a significant difference in the treatment outcome of the two patient groups in favour of borage seed oil.