Honest dosage analysis

AREDS Amounts Versus Label Amounts: The Arithmetic

Almost every eye supplement borrows its reputation from one trial, and almost none of them carries that trial's amounts. Doing the division is the single most useful thing a shopper can do, and it takes about two minutes once the units line up.

By OptiCore Pro Team · Last updated September 19, 2026 · 9 min read · Honest dosage analysis · Reviewed by Dr. Ashley Ott, OD

The formula, exactly as the trial gave it

The original AREDS report is the document the whole category rests on, and the formulation in it is specific: vitamin C 500 mg, vitamin E 400 IU, beta-carotene 15 mg, zinc as 80 mg of zinc oxide, and copper as 2 mg of cupric oxide. Daily, for an average of 6.3 years, in 3,640 people.

The finding was a reduction in progression to advanced age-related macular degeneration in the highest-risk group. The ten-year follow-up found the benefit held, which is what turns a single positive result into something durable.

Two negatives belong in the same paragraph. The cataract arm of the same trial found nothing, and the formula has never been shown to prevent macular degeneration developing in somebody who does not have it. The reputation is narrower than the shelf suggests.

Getting the units to line up

This is where most comparisons go wrong, and it is mechanical rather than difficult. Trial reports and supplement labels often use different units for the same substance, and a ratio calculated across mismatched units is worse than no ratio at all.

Conversions matter because a label and a trial report frequently use different units for the same substance, and a comparison in mismatched units is meaningless.

The vitamin E line is the one that catches people. Four hundred international units sounds like a different kind of quantity from seven milligrams, and it is not: it is about 268 mg of the same synthetic compound. Once converted, the comparison becomes arithmetic.

Beta-carotene is the other awkward one, because modern labels print vitamin A in retinol activity equivalents. Fifteen milligrams of supplemental beta-carotene is roughly 1,250 micrograms RAE, which is a great deal more than a multivitamin row.

Doing the division

The multivitamin column is the panel on the product this website sells, which is a reasonable stand-in for the category.

Four to twelve per cent is the range those ratios land in, and it is consistent enough to be a rule of thumb rather than a coincidence. A multivitamin is formulated against Daily Values; a trial formula is formulated against a hypothesis about a disease process. The two were never aiming at the same target.

A network meta-analysis ranking the individual nutrients is worth opening for anyone who wants to know which parts of the formula carry the weight, because the answer is not evenly distributed across the five.

Why a fraction is not a small version

This is the conceptual point the whole article exists for, and it is easy to state and easy to forget.

If a trial gives 500 mg and a capsule gives 60 mg, the capsule is not delivering twelve per cent of the benefit. Dose-response relationships in nutrition are rarely linear and are frequently threshold-shaped: below a certain intake nothing happens, above it an effect appears, and above that nothing further happens.

The honest position is that the smaller amount is a different intervention whose effects have to be argued on their own evidence. Sometimes that evidence is good. Correcting a deficiency at an ordinary Daily Value amount is well supported. It is simply not the same claim as the trial's.

Three ways the fallacy shows up

• A label naming the trial nutrients without the amounts, so a reader supplies the connection.
• Marketing copy citing a study for an ingredient at an amount the study did not use.
• A shopper assuming that more ingredients from the list means more of the effect, when amount decides it.

The copper corollary

Copper is in the AREDS formula for one reason and it is not an eye reason. Eighty milligrams of zinc oxide a day, sustained for years, competes with copper for absorption and depresses copper status. The trial added 2 mg of cupric oxide to prevent that.

This produces a useful rule for reading any label. If a formula carries high zinc and no copper, it has copied the trial carelessly. If it carries low zinc and no copper, its absence is correct, because there is nothing to offset.

It is also a rare case where an absence on a label is evidence of care rather than of cost-cutting, and it is worth knowing so that a reader does not count it as a failure.

What AREDS2 changed, and why

AREDS2 tested two additions to the original formula: lutein 10 mg with zeaxanthin 2 mg, and DHA 350 mg with EPA 650 mg. The omega-3 addition produced no further benefit at all.

The secondary analysis is what changed the product. It found lutein and zeaxanthin a better choice than beta-carotene, particularly in people with low dietary carotenoid intake, and the beta-carotene came out of the formula. The safety finding in smokers was the other half of that decision.

So the current benchmark formula is vitamin C 500 mg, vitamin E 400 IU, zinc 25 or 80 mg, copper 2 mg, lutein 10 mg and zeaxanthin 2 mg. Those six figures are what any label claiming the AREDS lineage should be measured against.

What a multivitamin amount is genuinely good for

Having spent an article on what these amounts are not, it is only fair to say what they are.

A row at fifty or a hundred per cent of a Daily Value is formulated to close a gap in somebody whose intake is short, every day, indefinitely, with no upper-limit concern. That is a genuinely useful thing and it is what the entire multivitamin category is for.

It is also the only claim a panel like this can support, which is why the most accurate description of a formula sharing three nutrients with AREDS at a tenth of the amounts is a competent daily multivitamin, sold with an eye framing.

Applying this to a label in two minutes

1. Find the four shared nutrients on the panel: vitamin C, vitamin E, zinc, and vitamin A or beta-carotene.
2. Convert the vitamin E into milligrams if the label uses international units.
3. Divide each by 500, 268, 80 and 15 respectively.
4. Look for lutein and zeaxanthin, and compare with 10 mg and 2 mg.
5. Check whether copper is present, and whether the zinc amount makes it necessary.

If the ratios come out near one, the label is following the trial. If they come out near a tenth, it is a multivitamin, which may still be exactly what you want for entirely different reasons. Either answer is worth having before paying, and the whole exercise is the first three rows of the scorecard.

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