A 240.5 mg blend and a 240 mg trial: the arithmetic of a proprietary blend

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

The TheYavue proprietary blend weighs 240.5 mg a capsule and holds ten ingredients. One of those ten, bilberry extract, has a published trial that used 240 mg a day on its own. The two figures are the same to within half a milligram, and that coincidence is the clearest way to show what a blend costs a reader.

What a proprietary blend is

The federal labelling regulation allows a dietary supplement to declare a group of ingredients as a blend: one total weight, contents listed in descending order of predominance, no individual amounts.

It is legal, it is common, and the stated justification is formula confidentiality. For a genuinely novel combination that argument carries some weight. In a category where every ingredient is public and the reference doses are printed in a trial protocol, it carries less.

TheYavue declares one. The line reads Proprietary Blend 240.5 mg with a dagger rather than a percentage, and beneath it ten names in order: lutein, bilberry extract, alpha lipoic acid, eyebright, zeaxanthin, quercetin, rutin, L-taurine, grape seed extract, lycopene.

At the label’s two-capsule direction, that is 481 mg a day shared ten ways.

The one arithmetic a blend total supports

A blend total looks like it tells you nothing. It tells you one thing, and it is a conclusion rather than an estimate.

Take the blend total. Multiply by the number of servings a day. That is the maximum any single ingredient inside it can contribute. Then compare that ceiling with each ingredient’s own published trial dose.

If one ingredient’s trial dose is larger than the whole daily blend, that ingredient cannot be at its studied amount. It requires no assumption about the split, no charity towards the manufacturer and no inside information. It is simply true.

For TheYavue the ceiling is 481 mg a day. Here is what that does and does not accommodate.

Trial doses are the figures printed in the papers cited at the foot of this article.

Bilberry: the ingredient whose trial dose is the whole blend

Bilberry is second by weight of the ten, which makes it one of the two largest components of this blend.

A 2020 randomised, double-blind, placebo-controlled trial gave 240 mg a day of standardised bilberry extract for twelve weeks and measured objective ciliary muscle contraction after screen work. That is a narrow, well-designed study with a measured endpoint, and it is the best evidence bilberry has.

The whole blend weighs 240.5 mg a capsule. One capsule cannot supply that trial dose from an ingredient that is one of ten. Across two capsules the ceiling rises to 481 mg, so 240 mg of bilberry would be half the daily blend on its own, with the remaining half shared between lutein, alpha lipoic acid, eyebright, zeaxanthin and five more.

That is not impossible. It is implausible on a formula whose front panel leads with lutein and zeaxanthin, and it would mean the two carotenoids the product is sold for are a small fraction of what is left.

And the reputation bilberry does not deserve

Worth one paragraph, because it is the thing most people think they know about this ingredient.

The night-vision reputation dates to a wartime story about pilots. A 2004 systematic review went looking for it across twelve placebo-controlled trials. The four most rigorous, conducted in healthy people with normal sight, were all negative.

So the useful claim for bilberry is the narrow, modern one about ciliary muscle and screen work, at a dose this blend cannot supply. The famous claim is the one the evidence does not support.

Alpha lipoic acid, at a larger scale

Third by weight, and the same problem with a bigger number.

A phase II randomised trial gave 1,200 mg a day of alpha lipoic acid in geographic atrophy. An earlier trial used 300 mg a day for three months and measured contrast sensitivity in people with diabetes.

Three hundred milligrams is the smaller of the two and it is still more than half the entire daily blend. Twelve hundred is two and a half times the whole of it.

Third of ten cannot reach either figure. That is a conclusion and not a criticism of the ingredient, which has a genuine and interesting literature behind it.

• Bilberry’s trial dose is 240 mg a day; the blend is 240.5 mg a capsule.
• Alpha lipoic acid’s smaller trial dose is 300 mg a day.
• The daily blend ceiling for everything together is 481 mg.
• AREDS2’s 12 mg of lutein and zeaxanthin fits comfortably.
• Six of the ten have no eye-outcome trial at any dose, so there is nothing to fall short of.

It is worth pausing on how unusual that coincidence is. Blend totals in this category cluster between about 100 mg and 500 mg, and trial doses for individual botanicals cluster between about 100 mg and 1,000 mg a day. The two ranges overlap heavily, which means the comparison above is not a trick played on one unlucky label. It is the ordinary result of putting eight or ten botanicals behind a single total, and almost every blend on this shelf fails it somewhere.

What makes this particular one legible is that the two numbers happen to land half a milligram apart. Nobody has to follow an argument; the figures sit next to each other and say the same thing.

What the ordering is worth

Descending order of predominance is legally required, which makes it the one genuinely reliable piece of quantitative information a blend publishes. It is worth more than most readers give it credit for.

The left column is genuinely useful and is the whole of what descending order publishes.

The most interesting thing that ordering reveals on this label is zeaxanthin at fifth. AREDS2 gave lutein and zeaxanthin at a five-to-one ratio, so lutein leading is expected and correct. Zeaxanthin sitting behind bilberry, alpha lipoic acid and eyebright is a formulation choice, and zeaxanthin is the pigment concentrated at the very centre of the macula.

A reader who cares about zeaxanthin specifically has learned something real from a label that publishes no figures at all.

The fair case for a blend

It would be easy to end an article like this with a flourish, and the honest version has two paragraphs of the other side in it.

Twenty-four ingredients for $39 to $59 a bottle is a real proposition. Assembled separately, a lutein product, a bilberry extract, an alpha lipoic acid, a B complex and a zinc-with-copper is five bottles, more money and five things to remember. The blend is how the price is achieved, and somebody who wants breadth rather than a verified number is being offered something reasonable.

And the printed half of this label is better than average. Fourteen rows with amounts and percentages, forms named throughout, zinc at 32 mg a day between the two AREDS arms, and copper at exactly the 2 mg that trial paired with it. That is not a formula assembled carelessly.

The trade is simply what it is. You get coverage and you give up verification, and the arithmetic above is what makes the size of that trade visible. The panel in full is on the supplement facts page.

References