WellnessBench

Filed Sep 3, 2026 · Sources: one systematic review and two randomized trials, PubMed · Market: US

Bilberry for eyes: what the trials tested, at what dose, and what they did not find

Bilberry sits in eye formulas on a night-vision claim that predates the screen-fatigue research. A systematic review of placebo-controlled trials found that claim not supported. Two smaller trials on screen fatigue used 240 mg and 480 mg a day of the extract, alone, and reported narrower results.

The short answer

"Bilberry for eyes" is really two separate questions. Night vision has a systematic review against it: the hypothesis is not supported by rigorous trials.

Screen fatigue has two small randomized trials behind it, at 240 mg and 480 mg of extract a day, each measuring one narrow eye-muscle metric, not comfort or eyesight in general.

The short answer: two different questions, and only one has trials behind it

Two different questions travel under one phrase, and only one of them has been pooled and re-checked.

The night-vision claim is the older of the two, and it is the one that has been pooled and re-checked. A 2004 systematic review in Survey of Ophthalmology gathered the placebo-controlled trials behind it, and that review is where this page starts.

It is not where the screen-fatigue claim comes from. That is a separate, newer line of research, on a separate question, at a different dose.

This page keeps the two apart. One has a negative review behind it. The other has two small trials, each with real limits.

Trial and review identifiers below are PMIDs, confirmed against PubMed on September 3, 2026 for our TheyaVue file.

What bilberry extract is on a label

On the label we transcribed for this cluster, the ingredient is printed exactly as "Bilberry Extract (Vaccinium myrtillus) (fruit)". It sits inside a proprietary blend, with no percentage or milligram figure of its own.

Neither of the two trials below records a standardization percentage in the abstract we read, and the label we transcribed does not print one either. That gap comes back in the last section of this page.

Label wording transcribed from TheyaVue's own supplement-facts panel, read 2026-09-03, per our TheyaVue recon.

Night vision: the systematic review that says the claim is not supported

The night-vision claim has been tested more than once, and the trials were pooled and re-checked.

Canter and Ernst reviewed placebo-controlled trials of bilberry and normal night vision. It was published in Survey of Ophthalmology in 2004. Their conclusion, verbatim:

"The hypothesis that V. myrtillus anthocyanosides improves normal night vision is not supported by evidence from rigorous clinical studies."Canter PH, Ernst E. Surv Ophthalmol 2004, PMID 14711439

Two details from that review matter for reading the claim honestly.

The four most recent and most methodologically rigorous randomized trials in the review were all negative.

And 11 of the 12 trials tested people with normal vision to begin with. They did not test people whose night vision was impaired by an eye condition. The review found no rigorous research in that second group either.

Source: Canter PH, Ernst E, "Anthocyanosides of Vaccinium myrtillus (bilberry) for night vision: a systematic review of placebo-controlled trials," PMID 14711439, read September 3, 2026.

Screen fatigue: two randomized trials, and what each one measured

Screen fatigue is a newer, narrower line of bilberry research, and it is not the same claim as night vision.

Two randomized, double-blind, placebo-controlled trials sit behind it. Neither measured "eye health" broadly. Each measured one specific eye-muscle or visual-function metric after screen work.

Kosehira 2020 · ciliary muscle 240 mg/day · 12 weeks

Standardized bilberry extract, display-task accommodation

109 healthy adults aged 20 to 60. The measured endpoint, HFC-1, tracks how well the eye's ciliary muscle recovers focus after a display-work task.

Post-task HFC-1 was better in the bilberry group than placebo at week 8 (p=0.014) and week 12 (p=0.017).

PMID 32106548, Nutrients 2020;12(3):600

Ozawa 2015 · screened for baseline fatigue 480 mg/day · 8 weeks

Bilberry extract, video display terminal workers

281 office workers aged 20 to 40 were screened; only the 88 with the lowest baseline critical flicker fusion (CFF) and near point accommodation scores were enrolled, and 80 completed.

The display-induced drop in CFF was blunted versus placebo (95% CI 0.10–1.60, p=0.023). Near point accommodation did not differ.

Participants' own ratings of eye fatigue, pain, heaviness, discomfort and a foreign-body sensation also improved more than placebo at week 8 (p<0.05), and the trial recorded no serious adverse events.

PMID 25923485, J Nutr Health Aging 2015;19(5):548–54

Both records confirmed against PubMed on September 3, 2026 for our TheyaVue file. Neither trial tested a finished multi-ingredient eye product.

The doses those trials used: 240 mg and 480 mg a day

Put next to each other, the two doses sit at opposite ends of a range, on different schedules.

Kosehira 2020, HFC-1 240 mg/day
Ozawa 2015, CFF 480 mg/day

Scale: 0 to 480 mg of bilberry extract a day, taken alone in each trial. Doses per PMID 32106548 and PMID 25923485, read September 3, 2026.

Both figures describe bilberry extract given by itself, not bilberry as a small piece of a larger formula.

That distinction becomes the whole question once bilberry shows up inside a multi-ingredient blend, which is what the next section works through.

Who paid for what, printed next to the finding

One of the two screen-fatigue trials names its own conflict of interest in the published paper.

"M.K. and N.M. are employees of Omnica Co., Ltd., Japan"Kosehira et al., Nutrients 2020, PMID 32106548, conflict of interest statement

Omnica Co., Ltd. is the maker of the standardized bilberry extract (SBE) the trial tested.

Printing that is the paper doing its job. It does not, by itself, invalidate the p-values above. But it does mean the 240 mg finding came from a trial with a financial stake in the result. An honest reading says so.

The 480 mg trial (Ozawa 2015) is the one where we found no such statement in the abstract record we read; we are not asserting one exists.

Conflict-of-interest statement quoted verbatim from the PubMed abstract record for PMID 32106548, read September 3, 2026.

Neither trial tested comfort, night driving, or a finished eye formula

It is worth being precise about what these two trials did not measure.

  • Neither trial's primary endpoint was subjective comfort; Kosehira measured a physical ciliary-muscle response and Ozawa measured flicker-fusion threshold and near point accommodation, though Ozawa's own subjective-symptom ratings improved too, at week 8.
  • Neither trial tested night driving, general "eye health," or any macular condition.
  • Near point accommodation, one of two endpoints in the Ozawa trial, did not differ from placebo.
  • Neither trial tested bilberry as part of a multi-ingredient product; both gave the extract alone.
  • The 2004 systematic review on night vision predates both screen-fatigue trials and answers a different question entirely.

What this means for you: "bilberry for eyes" is not one settled claim. It is a negative review on one question and two narrow, positive-but-limited trials on a different one.

What the trial dose means for a multi-ingredient eye formula

The 240 mg and 480 mg figures above describe bilberry extract taken alone. Most eye formulas do not sell bilberry alone.

On the label we transcribed for this cluster, bilberry sits inside a ten-name blend. The total is printed as 240.5 mg per capsule, at a serving of one capsule.

Proprietary Blend 240.5 mg: Lutein, Bilberry Extract (Vaccinium myrtillus) (fruit), Alpha Lipoic Acid, Eyebright, Zeaxanthin, Quercetin, Rutin, L-Taurine, Grape Seed Extract, Lycopene

Label panel, read 2026-09-03, per our TheyaVue recon

The seller's own instructions call for two capsules a day, which puts the full blend at 481 mg a day, split across ten named ingredients.

Bilberry is listed second in that blend, right after lutein. Federal labeling rules for proprietary blends require descending order by weight. So second place means bilberry cannot be the largest share. It is one of ten names sharing 481 mg.

For that 481 mg blend to reach even the lower trial dose, 240 mg, bilberry alone would need roughly half the entire blend. Nothing on the label states that share. The ordering rule alone cannot supply it either.

TheyaVue supplement facts panel showing the Proprietary Blend line at 240.5 mg with Lutein, Bilberry Extract and eight other ingredients named beneath it

This is the panel we transcribed: fourteen dosed actives above the fold, then the 240.5 mg Proprietary Blend line with ten names underneath it and no individual weights.

Bilberry Extract is the second name in that list, right after Lutein.

Blend composition and order per TheyaVue's own label panel, read 2026-09-03. Ordering rule: 21 CFR 101.36(c)(2), "descending order of predominance by weight," per our TheyaVue recon.

How to read a bilberry label without a percentage on it

A trial dose is a milligram figure. A label is often just a name, with no milligram figure attached. That gap is where a federal labeling rule matters.

Extract weight is not active-compound weight

"the weight of the ingredient shall be the weight of the dried extract"21 CFR 101.36(b)(3)(ii)

That rule governs any extract on a Supplement Facts panel, bilberry included. A milligram figure for "Bilberry Extract" is the weight of the dried extract material, not a stated weight of anthocyanins.

Neither the trials above nor the label we read print an anthocyanin percentage for the extract used. So even a bottle that printed "240 mg Bilberry Extract" on its own line would not automatically match the material Kosehira 2020 tested. "240 mg of extract" is not one fixed thing across manufacturers.

Two practical steps close most of that gap on any bottle in front of you.

1

Compare the trial dose to the blend total, not the ingredient name

An ingredient inside a blend can never weigh more than the blend's stated total. If the blend total is below the trial dose, the ingredient is too.

2

Read the directions before the panel

A panel written per single capsule, next to an instruction to take two, doubles every figure on that panel. Do the multiplication before comparing anything to a trial dose.

21 CFR 101.36(b)(3)(ii), read via govinfo.gov, September 3, 2026, per our TheyaVue recon.

Our reading, in plain terms

What the evidence supports

  • Two small randomized, placebo-controlled trials on bilberry extract and specific screen-fatigue measures, at 240 mg and 480 mg a day.
  • A statistically significant result on the endpoint each trial reported as its lead result, within that trial's own narrow measure.
  • A clearly stated conflict of interest in the 240 mg trial, printed by the authors themselves.

What it does not support

  • The claim that bilberry improves normal night vision; a systematic review found that not supported.
  • Any dose of bilberry as part of a named multi-ingredient blend, since neither trial tested a blend.
  • A guarantee that "Bilberry Extract" on two different labels is the same material at the same potency.

If the label does not print a bilberry dose, the honest alternatives are plain ones

We are not naming a competing brand as a villain here. The useful alternatives are formats, not names.

The bottle where this arithmetic actually applies

We put that arithmetic against a real bottle whose ten-ingredient blend totals 481 mg a day with bilberry listed second, and the review shows the whole panel, the directions that double it, and what the seller does and does not print.

If a bottle in front of you lists bilberry inside a blend with no individual dose, the next step is the full label read.

That review walks the whole panel line by line, including where bilberry sits and what the label leaves out.

Tip 1

Compare the trial dose to the blend total, not to the ingredient name. An ingredient inside a blend can never exceed the total the blend is declared at.

Tip 2

Check the directions before the panel. A per-capsule panel next to a two-capsule instruction doubles the blend total and changes the whole comparison.

Affiliate disclosure: the review linked below contains affiliate links, and a purchase made through them may earn us a commission at no extra cost to you. This page carries no affiliate link of its own.

Read our TheyaVue review

The full label panel, where bilberry sits in the blend, and what the seller does and does not print.

Questions people also ask

Does bilberry improve night vision?

A systematic review of placebo-controlled trials (PMID 14711439) concluded the hypothesis that bilberry anthocyanosides improve normal night vision is not supported by rigorous clinical studies, with the four most recent trials negative.

What dose did the eye-fatigue trials use?

240 mg a day of standardized extract for 12 weeks (PMID 32106548) and 480 mg a day for 8 weeks (PMID 25923485).

How long did those trials run, and who was in them?

Twelve weeks in 109 healthy adults aged 20 to 60, and eight weeks in 88 display workers selected from 281 screened for the lowest baseline flicker-fusion and near-point scores.

Who funded the bilberry screen-fatigue research?

The 2020 Nutrients trial prints its own conflict of interest statement: two of its authors were employees of the extract manufacturer.

Can a multi-ingredient eye supplement deliver a trial dose of bilberry?

Only if bilberry is a very large share of the formula. An ingredient inside a blend can never weigh more than the blend total, and blends do not print the split.

How we built this page

This is a reading of published trial records and one product label, not a lab test of our own.

  • The systematic review and both randomized trials were pulled from PubMed and confirmed on September 3, 2026, and are linked above by PMID.
  • The conflict-of-interest quote is verbatim from the PubMed abstract record for PMID 32106548.
  • The blend composition, order and total weight come from TheyaVue's own supplement-facts label panel, read 2026-09-03, per our TheyaVue recon.
  • The labeling rule on extract weight and ingredient order is quoted from 21 CFR 101.36, read via govinfo.gov, September 3, 2026.
  • We did not test any product for anthocyanin content, and we did not estimate a milligram figure for an ingredient the label does not itemize.
  • Nothing here is medical advice. A vision change, however small, is a conversation with an eye care professional, not a supplement page.

Two claims, two kinds of evidence

Night vision has a systematic review against it. Screen fatigue has two small, narrow trials, one of them run by the extract's own maker.

Neither describes what happens when bilberry is the second name in a ten-ingredient blend, and no label we read prints that share.

Reviewed by the Wellness Bench team · Published September 3, 2026