About a dozen randomized human trials and two meta-analyses form the entire serious evidence base for sea buckthorn. They cluster around six outcomes: dry eyes, skin, vaginal dryness, blood lipids, infections, and platelet function. Most are small and short. This catalog lists each one with its dose, duration, findings, and the limitation that keeps it honest.
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) | 2014 | 116 | 3 g/day oil | 3 months | About 3x better epithelial integrity vs placebo (OR 3.14); non-estrogenic | Single trial; modest vs topical estrogen |
| 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 |
| 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 | Blood pressure and lipids improved | Small, short, never replicated |
| 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.
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
One trial: 116 postmenopausal women, 3 grams of oil daily for three months. Vaginal epithelial integrity improved about three times more than placebo, through a non-estrogenic pathway. Positive, single, and honestly framed as a non-hormonal support option 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 on the front page of our research hub because it disciplines every immunity claim.
Vashishtha 2017 gave hypertensive adults 0.75 ml of seed oil daily for 30 days and saw blood pressure and lipids improve. Small, short, and never replicated, it sits against the pooled blood-pressure null from Geng 2022. 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 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 six 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. 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. A head-to-head against topical estrogen in about 200 women for six months, which would turn “non-estrogenic support option” into a placement doctors could actually use. The vaginal dryness page carries the current version of that comparison.
Who paid for all this
The funding map explains the catalog’s shape. Only two studies carry industry connections: Yang 2009 used a brand’s oil and ran in a journal outside the PubMed index, and Chan 2024 was funded by the brand whose oil it tested. The rest, from the dry-eye and vaginal trials to the two lipid meta-analyses, carries no such flag. 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, and platelet function. Most are small (12 to 250 participants) and short (4 weeks to 3 months). 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.