Hippophae rhamnoides L. · herb
Evidence tier: limited
A nutrient dense oil with strong evidence for mucosal dryness and skin barrier health.
The berry and seed oils carry an unusual fatty acid profile, notably palmitoleic acid (omega 7), plus alpha linolenic and linoleic acids, tocopherols, carotenoids and sterols. The proposed mechanism for the mucosal and ocular effects is that these fatty acids are incorporated into membrane lipids and into the lipid layer of the tear film and the vaginal epithelium, improving barrier quality and reducing water loss. The trials that support this measured tear film osmolarity and epithelial integrity, which are consistent with the story, so the mechanism is plausible and partially observed rather than merely asserted. The same unsaturated fatty acids and the berry flavonols are the likely basis of the antiplatelet effect.
Limited. Sea buckthorn is unusual in that placebo controlled human trials do exist, but almost all of them come from a single Finnish research group working with the oil producer, and the results are softer than the marketing implies. Dry eye: Larmo 2010 (Journal of Nutrition, PMID 20554904) reported that oral sea buckthorn oil attenuated the rise in tear film osmolarity over the cold season and improved symptoms. Attenuating a seasonal worsening is not the same as curing dry eye, and the effect sizes were small. Vaginal dryness: Larmo 2014 (Maturitas, PMID 25104582) randomised 116 postmenopausal women to 3 g of sea buckthorn oil daily for three months and found improved integrity of the vaginal epithelium (odds ratio about 3.1), while the vaginal health index, the more clinically meaningful measure, showed only a beneficial TREND, meaning it did not reach statistical significance. A trend is not a result. Skin barrier and blood lipid work exists at a similar scale. There is no Cochrane review, no regulatory monograph, and no independent replication by a group with no commercial interest in the oil. That combination, small trials, one research group, one supplier, unmet primary endpoints, is what limited looks like. Safety is mostly benign, with one signal worth respecting: in a crossover study in healthy men, sea buckthorn berry oil at 5 g daily for 4 weeks inhibited platelet aggregation (PMID 11120446), and isolated berry flavonols such as isorhamnetin show antiplatelet and anticoagulant activity in whole blood. The oil is therefore a plausible additive bleeding risk alongside warfarin, DOACs, aspirin, clopidogrel or high dose fish oil, and it is a sensible thing to stop before surgery. It is a food, and it is safe as a food, but the antiplatelet effect is a real pharmacological action and it should not be silently stacked with blood thinners.
3 g of sea buckthorn oil daily for three months is the dose that produced the vaginal atrophy findings; 2 to 5 g daily of oil is the range used across the dry eye and platelet studies. Oil, not juice or powder, is what was tested. Improvements in the trials took two to three months to appear, not days.
500 to 2000 mg oil daily with food.
Onset: ~90 days
Generally very safe.
Pregnancy: caution
Breastfeeding: caution
Active compounds: palmitoleic acid (omega 7), alpha linolenic acid, linoleic acid, tocopherols, carotenoids, isorhamnetin, quercetin
Remedies using Sea Buckthorn · Browse by body system · Check it against what you take
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.