Eyebright: fourth by weight on the TheYavue label, and no oral trial anywhere

By TheYavue Team · Last updated September 19, 2026 · 8 min read · The evidence · Reviewed by Dr. Linh Chieu, OD

Eyebright is named for this exact use. It is the fourth-heaviest ingredient in the TheYavue proprietary blend. And four PubMed searches for a clinical trial of oral Euphrasia officinalis returned nothing at all, which makes it the clearest refused claim on this website.

What the search actually returned

Four separate PubMed searches were run for this build: for a clinical trial of Euphrasia officinalis, for eyebright clinical trials generally, for Euphrasia in conjunctivitis, and for eyebright in an ophthalmic context.

Between them they returned two human-relevant records. Neither is a trial of eyebright taken by mouth, and neither has anything to do with vision.

This is worth stating flatly because it is unusual. Most supplement ingredients have a thin literature rather than an absent one: a small trial, an underpowered result, something in the wrong population. Eyebright has no randomised trial of the oral route at all.

Four PubMed searches across this build session returned the first two records and nothing else.

The one human record, and why it is not the claim

The 2000 record is a prospective cohort trial of single-dose Euphrasia eye drops in conjunctivitis, published in the Journal of Alternative and Complementary Medicine.

Three things about it matter and none of them is a criticism of the study, which is perfectly respectable for what it is.

It is a cohort rather than a randomised comparison, so there is no control group and conjunctivitis resolves on its own. It is a topical preparation dropped onto the surface of the eye, not a capsule swallowed and metabolised. And the condition is inflammation of the conjunctiva, which has nothing to do with the macula, the retina or visual function.

The 2014 record is an in-vitro assay of eyebright extract on cultured human corneal cells. That is a laboratory observation about cells in a dish, and it is a reasonable early step in investigating a plant. It is not evidence about a person.

So the honest position is that eyebright, taken orally, for sight, has no clinical evidence. Not weak evidence. None.

Why fourth by weight matters

Federal labelling rules require a proprietary blend to list its contents in descending order of predominance. That ordering is the one reliable piece of quantitative information a blend publishes.

On this label eyebright is fourth of ten. It weighs more than zeaxanthin, more than quercetin, more than rutin, more than taurine, more than grape seed and more than lycopene.

The blend is 240.5 mg a capsule. Every milligram of it that is eyebright is a milligram that is not lutein or zeaxanthin, and lutein and zeaxanthin are what the front of the bottle leads with.

That is the real cost of an ingredient with no evidence behind it. It is not that it does harm; at this scale it almost certainly does nothing at all. It is that it takes up space on a label with a finite total, ahead of an ingredient that has a five-year randomised trial behind it.

• Eyebright is fourth of ten by weight in the blend.
• It outweighs zeaxanthin, which AREDS2 randomised at 2 mg a day.
• It has no randomised trial by the oral route, for any outcome.
• Its only human record is eye drops in conjunctivitis.
• Every milligram of it is a milligram of something else.

The pattern this belongs to

Eyebright is the clearest case on this label and it is not the only one. Four different substitutions recur across this category, and once you can name them the whole shelf reads differently.

All four substitutions are common across this category and none of them is a lie. They are simply not the claim the label implies.

Why each one is tempting

Every one of those four starts from a true statement. Euphrasia drops were studied in conjunctivitis. Bilberry does have a famous story. Taurine depletion really does damage the retina. Serum lycopene really is lower in people with macular degeneration.

The step that fails is always the same: a true finding in one context is offered as though it applied to another. Topical becomes oral. Anecdote becomes evidence. Deficiency becomes supplementation. Association becomes effect.

The bilberry review is the best illustration, because somebody actually went and checked. Twelve placebo-controlled trials; the four most rigorous, in people with normal sight, all negative. The story survived the checking anyway, which is how these things work.

Why an ingredient like this ends up on a label

Two reasons, and neither requires bad faith.

The first is the name. Euphrasia officinalis is called eyebright in English and its traditional use is documented back centuries. A formulator assembling an eye supplement who sees a plant literally named for the organ has an obvious candidate, and the absence of trials is easy not to notice because nobody looks for absence.

The second is that an ingredient count sells. Twenty-four reads as better value than six, and botanicals are cheap relative to 10 mg of lutein. A blend that includes eyebright costs very little more than one that does not and reads as more comprehensive.

Neither of those is a scandal. Both are ordinary commercial logic, and both are the reason a reader has to do the checking themselves.

One last point about how this check should feel when you run it yourself.

The right response to finding nothing is not outrage. Most traditional botanicals have never been tested properly, and a supplement industry that only used ingredients with randomised trials behind them would be a very short shelf. The useful response is proportion: an untested ingredient at the bottom of a blend is a passenger, and an untested ingredient fourth by weight is displacing something better.

Eyebright here is the second kind, which is why it gets an article rather than a footnote.

What this does and does not say about the product

Being clear about the scope of this, because one weak ingredient does not condemn a formula.

It does not say eyebright is dangerous. At a fraction of a 240.5 mg blend it is almost certainly inert, and no safety signal exists for it either.

It does not say the product does nothing. Lutein leads the blend, zeaxanthin is in it, and the printed half of this panel carries all four AREDS nutrients with the zinc and copper well placed.

What it does say is that a label of twenty-four ingredients is not twenty-four reasons to buy. On this one, by this desk’s reading, about seven are doing very little: eyebright, quercetin, rutin, taurine, selenium, chromium and calcium. A shorter list at published doses would be a better formula and a less impressive label.

That reading, ingredient by ingredient, is on the ingredients page, and the four claims this desk refused outright are recorded at the foot of it.

References