as well as with dietary supplements or medications containing borage-derived ingredients
Borage (Borago officinalis), also known as starflower, belongs to the borage family (Boraginaceae). Originally known in the Orient and the Mediterranean region, it has been cultivated in Germany since the Middle Ages as a spice and medicinal plant (hence the suffix “officinalis”) and is now also found growing wild.
Borage is an annual herb growing 50–75 cm tall, with hairy stems and elongated leaves growing directly from the stem. The blue flowers and later fruit clusters are grouped at the top of the plant. The flowering period is from May to August. It is related to comfrey, which looks similar but forms rhizomes and also belongs to the Boraginaceae family.
As medicinal plants, the flowers in particular were used for a wide variety of indications (Boraginis flos, Flores boraginis); “inflammation,” “rheumatism,” and “blood purification” are also historically cited, while the leaves, due to their cucumber-like taste, are used more in the kitchen and specifically in Frankfurt green sauce.
Borage seeds consist of 1/3 oil (Boraginis officinalis oleum raffinatum, Boraginis oleum, DAC). This oil contains a significant amount of gamma-linolenic acid (GLA) as well as a range of other fatty acids (35–38% linoleic acid, 16–20% oleic acid, 10–11% palmitic acid, 3.5–5.5% gadoleic acid (11Z-eicosenoic acid), 3.5–4.5% stearic acid, 1.5–3.5% erucic acid, approximately 1.5% nervonic acid, and less than 1% each of arachidic acid, behenic acid, palmitoleic acid, vaccenic acid, myristic acid, eicosadienoic acid, and alpha-linolenic acid)[6].
Borage seed oil is sold as an over-the-counter dietary supplement in pharmacies in strengths of 500, 750, and 1000 mg of oil with a stated GLA content of approximately 20%, as well as in 240 mg GLA capsules. Online, 250-ml bottles are also available for culinary use. It has little to no taste of its own. Some preparations contain additional fatty acids or vitamin E. The indicated use is “as a substitute for unsaturated fatty acids.” Borage seed oil is also marketed as a skin care product.
Use of borage for rheumatoid arthritis (RA)
Results of a PubMed search ((Borago[Title]) OR (Borago[Text Word]) OR (Borage[Title]) OR (Borage[Text Word])) AND (Arthritis[text word]) yielded 19 results, of which 11 qualified for a full-text analysis. The search ((Borago[Title]) OR (Borago[Text Word]) OR (Borage[Title]) OR (Borage[Text Word])) AND (Rheum [text word]) yielded no further results.
In a study by the University of Shiraz (Iran), 51.4% of 500 surveyed patients with RA reported using herbs in general, and 36.8% reported using borage; however, the rate of borage use was not significantly higher than that of controls without RA [2].
No studies on the use of the whole plant, leaves, or flowers were found. The published studies are limited to the oil extracted from borage seeds.
The high content of gamma-linolenic acid (GLA) in the seeds is considered a potential active ingredient in borage seed oil. In an 18-month randomized study, fish oil and borage seed oil—alone and in combination (but not a placebo)—were compared as add-ons to standard RA therapy; 150 patients with RA were randomized. Approximately half of the patients could be evaluated. A moderate improvement in DAS and CDAI was observed, with no difference between the groups [3]. Olendzkie et al. reported from the same study a significant improvement in LDL and HDL levels in the overall cohort over time. They found no differences between the arms. No relevant changes in erythrocyte sedimentation rate or C-reactive protein were documented [4].
Leventhal et al. observed a 36% reduction in the number of painful joints and a 28% reduction in the number of swollen joints in a small (37 patients) 24-week randomized, placebo-controlled study of RA patients treated with borage seed oil [5]. Zurier et al. describe a randomized, placebo-controlled study involving 56 patients, 41 of whom were evaluable after 6 months. Among those receiving the active treatment, 14 out of 22 achieved at least a 25% improvement in joint symptoms, compared to 4 out of 19 in the placebo group [6]. Macfarlane et al. view these two studies as evidence of a probable effect; further studies on the substance are not mentioned in their review [7].
In a three-arm randomized study, Belch et al. treated 16 patients with RA with GLA from evening primrose, 15 with a GLA-fish oil combination, and 18 with placebo. They documented a reduction in NSAID requirements after 12 months [8]. In a review, the author also attributes this effect to borage seed oil due to its comparable composition [9].
Cameron et al. conducted reviews in 2009 and 2011 on studies involving GLA for RA, summarizing 7 studies each on evening primrose oil, black currant oil, and borage oil. The data indicate a required dose of at least 1400 mg GLA/day, while 500 mg GLA/day was not effective. The data show a reduction in pain intensity (mean difference (MD) of -32.83 points, 95% confidence interval (CI) -56.25 to -9.42 on a 100-point pain scale) and a reduction in functional impairment (MD -15.75%, 95% CI -27.06 to -4.44%) [10, 11].
In an animal model using rats, GLA was associated with less inflammation than placebo in cases of acute crystal-induced arthritis and immunologically triggered arthritis induced by Freud’s adjuvant; a 5-fold higher ratio of GLA to arachidonic acid under GLA therapy was cited as an explanation [12].
Other Indications
Literature searches for the indications “lupus,” “spondylitis,” and “fibromyalgia” yielded no results in each case.
The search query ((Borago[Title]) OR (Borago[Text Word]) OR (Borage[Title]) OR (Borage[Text Word])) AND (Pain[text word]) yielded 7 results, 6 of which are already listed under the “Arthritis” indication. An additional review recommends 1–3 g of GLA (from the three sources mentioned: borage, black currant, and evening primrose) for pain management without providing its own study data [13].
The plant contains pyrrolizidine alkaloids (amabiline, intermedine, lycopsamine, supinine, thesin). These are classified as genotoxic , carcinogenic, and hepatotoxic , and their consumption should be avoided [14]. There are further statements to this effect [15-17], and in the European Union, maximum levels for pyrrolizidine alkaloids have been established effective 07/2022 (Regulation (EU) 2020/2040). Due to its high pyrrolizidine content, Borago should also no longer be used for pharmaceutical purposes [18].
The Cochrane review of 7 studies on GLA in RA documented an increase in adverse events in the active treatment group (20% versus 3% in the placebo group) (relative risk 4.24, 95% CI 0.78 to 22.99) [11]. A study by Kast identifies a potential theoretical risk associated with borage seed oil due to reported prostaglandin E antagonism and possible teratogenic effects, without providing concrete evidence for this [19].
The scientific evidence is sufficient to warn against the regular use of borage leaves and flowers. The pyrrolizidine alkaloids contained in borage are potentially teratogenic, carcinogenic, and hepatotoxic.
GLA, a component of borage seed oil, has demonstrated a limited anti-inflammatory effect and a slight improvement in the lipid profile in animal studies of crystal-induced arthritis and Freund’s adjuvant-induced arthritis in rats, as well as in small controlled studies involving patients with rheumatoid arthritis. The effect requires a daily dose of at least 1500 mg of GLA and is comparable to the effect of fish oil. A combination of plant-based and animal-based unsaturated fatty acids is no more effective than the individual substance. Although some of the studies were systematic, controlled, and conducted with validated outcome measures, they involved very small patient cohorts, high dropout rates, and were calculated without a selection strategy for dropouts; one study lacked a placebo arm. Due to this insufficient data, therapeutic use is not recommended.
GLA derived from borage seed oil from certified manufacturers or from other plant sources can be used as an alternative to other oils, vegetables, nuts, algae, or fish containing omega-3 fatty acids as part of a health-oriented diet in accordance with the Commission’s recommendation [20], if the latter cannot be used, for example, in cases of allergies.
From a rheumatological perspective, the published data and regulatory status do not justify the use of borage seed oil preparations as an adjunctive treatment for rheumatic diseases.
| Borago officinalis | Leventhal LJ, et al., 1993 [5] | Randomisierte, doppel blinde, Placebo kontrollierte Studie, 24 Wochen. 37 Patienten eingeschlossen Einnahme von 1,4 g GLA (Gammalinolensäure) pro Tag, als Borretsch-samenöl. Placebo-kapseln enthielten Baumwoll-samenöl. | Nach 6 Monaten zeigten sich bei RA-Patienten, die mit Borretschsamenöl behandelt wurden im Vergleich zur Placebogruppe signifikante Verbesserungen bei der Anzahl und den Werten schmerzhafter Gelenke, den Werten für Gelenkschwellungen, der ärztlichen Gesamtbeurteilung und den Schmerzen. Bei keinem Patienten in der Behandlungsgruppe kam es zu einer Remission. 7 Pat. (36,8 %) hatten eine deutliche Verbesserung und 7 Pat. (36,8 %) hatten keine Verbesserung. In der Placebogruppe kam es bei 1 (5,6 %) zu einer Verbesserung und bei 12 (63,2 %) nicht. |
| Zurier RB, et al. 1996 [6] | Randomisierte, doppel blinde, Placebo kontrollierte Studie, 6 Monate mit initial 56 RA-Patienten. Nach 6 Monaten erhielten beide gruppen GLA Ausgewertet nach 6 Monaten 22 Verum 19 Placebo Nach weiteren 6 Monaten Verum 21, Placebo-Verum 14 Patienten erhielten entweder 2,8 g/Tag GLA aus Borretsch-samenöl oder Placebo (Sonnenblumenkernöl). | mit Borretschsamenöl behandelten Patienten zeigten im Vergleich zu den Placebo-Patienten eine signifikante Verbesserung: - bei der Anzahl der schmerzempfindlichen Gelenke - der Anzahl der geschwollenen Gelenke - der Punktzahl der schmerzempfindlichen Gelenke - den auf einer visuellen Analogskala (VAS) gemessenen Schmerzen - der Punktzahl im Fragebogen zur Gesundheitsbewertung - Insgesamt zeigte nach 6 Monaten ein größerer Prozentsatz der Behandlungsgruppe (64 %) im Vergleich zur Placebogruppe (21 %) eine signifikante Verbesserung, die als Verbesserung von mindestens 25 % bei mindestens vier Messgrößen definiert wurde. (6,5x höhere Wahrscheinlichkeit einer bedeutsamen Verbesserung als Placebo) - In den zweiten 6 Monaten nach Umstellung von Placebo auf GLA Besserung auch bei den verbleibenden 14 Patienten, bei Beibehaltung von GLA Konsolidierung | |
| Olendzki BC, et al., 2011 [4] Reed GW et al., 2014 [3] | Randomisierte, doppel blinde, 3-armige Studie, 18 Monate mit initial 156 RA-Patienten (53 Borretsch-Öl 1,8g/Tag, 56 Fischöl 3,5g/Tag, 47 beides). Nach 9 Monaten wurden insgesamt 83 Patienten, nach 18 Monaten 69 Patienten erfasst. | Kein Einfluss auf Gewicht, CRP, BSG Reduktion von Cholesterin, LDL und Triglyceriden, Steigerung von HDL Reduktion des DAS um 1,33 (9 Monate und 1,53 (18 Monate) (Borretschöl); 1,18 und 1,28 (Kombination) und 1,56 und 1,45 (Fischöl) Anstieg des Sharp Score um 0,69 (Borretschöl), 1,07 (Kombination) und 2,26 (Fischöl) |
Last updated: September 28, 2024