About a dozen randomized human trials and two meta-analyses form the entire serious evidence base for sea buckthorn. They cluster around seven outcomes: dry eyes, skin, vaginal dryness, blood lipids, infections, platelet function, and now constipation. Most are small and short. This catalog lists each one with its dose, duration, findings, and the limitation that keeps it honest.
This catalog is the spine of the research desk. Every graded claim elsewhere on the site traces back to a row in the table below.
The master table
| Trial | Year | n | Dose | Duration | What it found | Limitations |
|---|---|---|---|---|---|---|
| Geng (meta-analysis) | 2022 | 15 RCTs pooled | varies | 4-12 wk trials | TG, total cholesterol, LDL down; HDL up; strongest in abnormal lipids. Null: glucose, BP, BMI | Underlying trials small and short; lab numbers, not events |
| Guo (meta-analysis) | 2017 | 11 RCTs pooled | varies | weeks | Same lipid conclusions, independent pool | Same structural limits |
| Larmo (dry eye) | 2010 | 100 | 2 g/day oil blend, split with meals | 3 months | Smaller tear-osmolarity rise; max redness 6% vs 36%; burning 12% vs 32% | Single trial; 23 other symptoms null |
| Jarvinen (mechanism) | 2011 | dry-eye cohort | 2 g/day | 3 months | Tear-film fatty acids did NOT differ between groups | Mechanism unanswered |
| Larmo (vaginal, ORAL) | 2014 | 116 | 3 g/day oral oil | 3 months | About 3x better epithelial integrity vs placebo (OR 3.1, 95% CI 1.11-8.95), non-estrogenic | Single trial. Compliant-only analysis was non-significant (OR 2.9, 95% CI 0.99-8.35) |
| Yu (vaginal, TOPICAL) | 2025 | 368 of 377 | Compound SB vaginal suppository (topical, not oral) | 2 weeks | Both active arms beat no pretreatment on colposcopy readiness (P below 0.001), with no significant difference between suppository and estrogen ointment. No systemic side effects vs estrogen's 5.6% breast discomfort and 4% dizziness or headache | Topical route, different product from Larmo. Compound formula, open-label, no pre-set non-inferiority margin, local vaginal discomfort in both arms, colposcopy-prep setting rather than a dryness-symptom trial |
| Yang (skin) | 2009 | 60 (30 oral) | 2 g/day SBA24 oil | 3 months | Hydration +48.6%, elasticity +25.8% on instruments | No placebo arm for oral; brand-linked oil |
| Chan (skin) | 2024 | 40 | 1 g/day Omegia oil | 12 weeks | Hydration +8%, collagen density +10%, texture +14%, pores -15% | Industry-funded; small n |
| Larmo (infections) | 2008 | about 250 | 28 g/day whole berries | 3 months | No effect on colds; CRP (inflammation marker) decreased | Food dose, healthy adults |
| Morone (constipation) | 2026 | 90 | 500 mg/day fruit extract | 28 days | Spontaneous complete weekly bowel movements 1.5 to 2.6; Bristol stool 1.4 to 3.5; both p below 0.001; no change on placebo. Null: flatulence, SF-12 quality of life | Industry-sponsored (EPO S.r.l.); single 28-day trial; fruit extract, not the oil |
| Larmo (low-dose berries) | 2009 | healthy adults | low-dose berries | weeks | Lipid and flavonol measures at food doses | Small, healthy participants |
| Larmo (metabolomics) | 2013 | overweight women | berries vs bilberry | crossover | Effects differed by baseline metabolic profile | Crossover, specific population |
| Vashishtha (hypertension) | 2017 | hypertensive adults | 0.75 ml/day seed oil | 30 days | Reported blood pressure and lipid improvement | RETRACTED 2026 (figure integrity). Not usable as evidence |
| Johansson (platelets) | 2000 | 12 | 5 g/day berry oil | 4 weeks | Clear drop in platelet aggregation | 12 healthy men; very high dose |
The lipid family
Two independent meta-analyses, Geng 2022 pooling 15 randomized trials and Guo 2017 pooling 11, converged on the same result: sea buckthorn significantly lowers triglycerides, total cholesterol, and LDL while raising HDL, with effects concentrated in people whose lipids were abnormal to start. The same Geng analysis found no significant effect on fasting glucose, blood pressure, or BMI. That convergence is the strongest card this plant holds, and the cholesterol page translates it for non-scientists. Matching the doses in this table means counting grams of oil rather than capsules, and our capsules guide scores products on whether that number appears on the label at all.
The dry-eye family
The flagship single trial: 100 adults, 2 grams of blended seed-and-berry oil daily for three winter months, randomized, double-blind, placebo-controlled. Tear osmolarity rose less in the sea buckthorn group, and the worst redness and burning days dropped sharply. Twenty-three other measured symptoms did not move, and we print that. The 2011 follow-up found tear-film fatty acids unchanged, so the mechanism remains open. Full dissection on the dry-eye trial page.
The skin family
Two trials, two generations of design. Yang 2009 measured large effects (about 49% hydration, 26% elasticity) with instruments but gave the oral arm no placebo. Chan 2024 measured smaller effects (8% hydration, 10% collagen density) against a real placebo, with industry money attached. They triangulate each other, and the skin studies page does the full autopsy.
The women’s health family
Two trials now, and they split by route. Oral: Larmo 2014 gave 116 postmenopausal women 3 grams of oil daily for three months, and vaginal epithelial integrity improved about three times more than placebo through a non-estrogenic pathway. Topical: a 2025 trial randomized 377 postmenopausal women before a colposcopy to a vaginal sea buckthorn suppository, an estrogen ointment, or no pretreatment, and among the 368 who finished, both treatments made the exam readable and the two of them came out statistically indistinguishable, with none of estrogen’s systemic side effects on the suppository side. That last phrase does a lot of work, so read it carefully. The trial set no non-inferiority margin, so it detected no difference rather than proving the two equal. Keep the routes apart too. The head-to-head with estrogen belongs to a local suppository, a compound formula placed in the vagina, not to the oral capsules Larmo tested. Both are single trials of their kind, and both are honestly framed as support rather than a replacement for anything.
The infection and cardiovascular outliers
Larmo 2008 gave about 250 healthy adults 28 grams of whole berries daily for three months and found no effect on colds, with a mild drop in the inflammation marker CRP. We keep that null in front of every immunity claim on this site because it disciplines all of them.
Vashishtha 2017 reported that hypertensive adults taking 0.75 ml of seed oil daily for 30 days saw blood pressure and lipids improve. That paper is gone. Clinical Nutrition retracted it in 2026 over duplicated images across its figures, which the corresponding author could not explain. So the pooled blood-pressure null from Geng 2022 now stands with nothing arguing against it. We kept the row in the table above, marked retracted, because a withdrawal readers can see is more useful than a citation that quietly disappears. Johansson 2000 gave 12 healthy men 5 grams of berry oil daily for four weeks and measured clearly reduced platelet aggregation: tiny, high-dose, and the reason our blood-thinner page exists.
The constipation trial
The catalog’s first gut trial arrived in 2026. Morone and colleagues randomized 90 adults with chronic idiopathic constipation to either a 500 mg sea buckthorn fruit extract or a matching placebo, double-blind, for 28 days. Spontaneous complete bowel movements rose from about 1.5 to 2.6 per week on the extract while placebo held flat, and stool consistency normalized on the Bristol scale, both at p below 0.001. Bloating, abdominal pain, and heaviness eased as well. Flatulence did not separate from placebo, and the SF-12 quality-of-life score barely moved, which puts a ceiling on how much a reader should expect a month of this to change their life. No adverse events were reported. The honest asterisk is the funding. The extract came free from EPO S.r.l., the named sponsor, so this is a brand-funded study standing alone until an independent group repeats it. We treat it as a real but single, brand-funded human result that needs replication, and the constipation page leads with it and its caveats.
The low-dose and crossover studies
Three more trials fill out the catalog’s middle. Larmo 2009 gave healthy adults low food-level doses of berries and tracked cholesterol, triglyceride, and flavonol measures: nutrition research at food doses, not supplement doses. Larmo 2013 ran a crossover in overweight women comparing sea buckthorn against bilberry and found the effects differed by each woman’s baseline metabolic profile, an early hint that who takes the berry shapes what it does. And the Jarvinen 2011 follow-up re-analyzed the dry-eye cohort for mechanism, finding tear-film fatty acids unchanged. None of these stands alone as proof of anything, and each one disciplines the claims the bigger trials make.
How the families compare
Read across the seven families and a grading pattern emerges. Lipids hold the deepest evidence: two meta-analyses, dozens of pooled trials, one direction. Dry eyes hold the best single study: 100 people, placebo-controlled, seasonally timed. Skin and vaginal health each hold one to two positive trials with real caveats. Infections hold a clean null at food doses. And platelets hold a small high-dose signal that matters for safety more than benefit. Constipation is the newest and thinnest, a single brand-funded extract trial that still needs an independent repeat. A plant whose evidence is this uneven is normal. A website that admits it is rarer.
The trials that do not exist
The fastest way to read this catalog is to notice what is missing from it. No human trial has tested sea buckthorn for cancer, and nothing in the verified file touches cognition, sleep, or mood. No trial has tested it for weight loss, and the pooled BMI null is the closest thing to an answer the science offers, which the weight loss page treats with the seriousness a null deserves. No trial has tested it for blood sugar control, and the fasting-glucose null says why the blood sugar page stays cautious. Absence of trials is not absence of benefit. It is absence of knowledge, and honest pages price it accordingly.
What would settle the top three questions
Lipids. A trial enrolling thousands of people with abnormal cholesterol, run for years, measuring heart attacks and strokes rather than lab panels. No supplement has ever funded one, so the realistic next step is a 12-month marker trial with follow-up.
Dry eyes. An independent lab, a different climate, about 300 participants across all seasons. One team’s single winter study is a lead until another team finds the same thing.
Vaginal dryness. For the oral capsules, a straight replication of Larmo 2014 at 3 grams daily, run longer than three months. A 2025 trial already found a topical sea buckthorn suppository no different from estrogen at getting a cervix ready for colposcopy, but that result belongs to a local product, it was not designed to prove equivalence, and it does not carry over to swallowing oil, so the oral question stays open. The vaginal dryness page keeps the two routes separate.
Who paid for all this
The funding map explains the catalog’s shape. Three studies carry industry connections. Yang 2009 used a brand’s oil and ran in a journal outside the PubMed index, Chan 2024 was funded by the brand whose oil it tested, and Morone 2026 tested a fruit extract that its sponsor, EPO S.r.l., supplied free of charge. The rest, from the dry-eye and vaginal trials to the two lipid meta-analyses, carries no such flag, and the 2025 suppository trial goes one better by stating that its authors paid the costs themselves and took no outside money. Funding proves nothing in either direction. It tells you where to look for inflation, and the six checks page turns that instinct into a drill.
How to read this catalog
Count the pattern, not the promises. Every positive here is one to three small trials deep. Every null is published next to its positive. When a label or blog quotes any of these trials without its limitation column, you now own the limitation column. The doses behind each row are tabulated on the study dosages page, and how we research documents the grading method itself.
Frequently asked questions
How many human clinical trials of sea buckthorn exist?
The verified core is about a dozen randomized controlled trials plus two meta-analyses pooling them, covering dry eyes, skin, vaginal dryness, blood lipids, infections, platelet function, and now constipation. Most are small (12 to 368 participants) and short (2 weeks to 3 months). One of them, Vashishtha 2017 on blood pressure, was retracted in 2026 and no longer counts. That is a real but young evidence base, stronger than most supplements and far short of any drug.
What is the strongest sea buckthorn trial evidence?
Blood lipids, where two independent meta-analyses (15 and 11 randomized trials) found the same result: lower triglycerides, total cholesterol, and LDL, with the effect concentrated in people who started with abnormal levels. The strongest single trial is the 100-person dry-eye study, randomized, double-blind, and placebo-controlled.
Why are there so few sea buckthorn trials?
Economics. A drug trial pays for itself through patent exclusivity, and nobody can patent a berry, so no company recovers a nine-figure trial budget from sea buckthorn. What exists comes from small academic groups running modest trials on modest budgets. That is why the catalog is a dozen small studies instead of a drug-style development program, and why every page on this site grades accordingly.