How to choose a cognitive supplement
This category is unusually hard to shop in, because the thing being sold cannot be felt reliably and the thing being measured cannot be measured at home.
Four questions do most of the work: is every amount published, does each amount match a researched dose, is the ingredient studied for the outcome you want, and what does it cost a day?
Most formulas in this category fail the first question, and a formula that fails the first cannot be assessed on the other three.
Why this category is harder than most
Three things make cognitive supplements uniquely difficult to buy well, and it is worth naming them before any advice.
The outcome is invisible
You cannot weigh your focus. A protein powder either builds muscle or does not, measurably. Cognition is felt, and feelings follow sleep, caffeine and mood far more than capsules.
No home instrument
Expectation does real work
Placebo effects are strongest exactly where outcomes are subjective. Deciding to take your brain seriously changes behaviour, and the behaviour changes the outcome.
Not a criticism of you
The ingredients are individually plausible
Almost everything in this category has a mechanism story. Plausibility is cheap; the amounts are where formulas separate.
Plausible is not proven
None of that means nothing works. It means the ordinary consumer signals — how it feels, what reviewers say, how impressive the ingredient list looks — are unusually unreliable here, and the label is unusually important.
Question one: is every amount published?
This is a gate rather than a question. A formula that hides its amounts cannot be assessed on anything else, so it either passes here or the other three questions do not apply.
- Open label: every ingredient has a milligram figure. You can check every one against the literature.
- Partial blend: some ingredients quantified, the rest inside a blend. CogniMary is here — four quantified, eleven not.
- Full blend: one number for everything. You can derive ceilings and nothing else.
- No panel at all: walk away. If a seller will not print a panel, no argument they make about the formula can be checked.
The ceiling technique from the panel guide gets you partway back from the second and third of those, which is why it is worth learning. It does not get you all the way.
Question two: does the amount match the research?
An ingredient at a tenth of its trial dose is decoration. This is the single most common failure in this category and it is invisible unless you look it up.
| Ingredient | Dose used in trials | What the trials measured |
|---|---|---|
| Ginkgo biloba | 120–240 mg a day | Cognitive decline; the largest trial was null |
| Bacopa monnieri | 300 mg a day, 12 weeks+ | Speed of attention |
| Alpha-GPC | 600 mg a day | ADAS-cog in mild cognitive impairment |
| L-theanine | 200 mg, single dose | Acute attention and reaction time |
| Alpha lipoic acid | 600 mg a day | No qualifying dementia trials found |
| Lutein + zeaxanthin | 10 mg + 2 mg | Eye health; cognition arm was null |
| Berberine | 1,500 mg a day | Glucose and lipids, not cognition |
Scroll this table sideways →
Two things fall out of that table. First, the doses are large — several hundred milligrams each — which is why a small blend cannot hold many of them. Second, several of the best-known ingredients have their strongest evidence for something other than memory.
Question three: is it studied for what you want?
An ingredient with a real literature behind it can still be in the wrong product. This is the quietest failure of the four because every part of it is technically true.
- Berberine has a substantial metabolic literature and, as far as we could establish, no human cognition evidence at all.
- Cinnamon has glucose and lipid trials. Its cognition record is not one we could find.
- Lutein and zeaxanthin have strong eye-health evidence. The AREDS2 cognition substudy found no difference between any supplement group.
- Alpha lipoic acid has a real record in diabetic peripheral neuropathy, which is not what a focus supplement is sold for.
A formula built from ingredients like these can be described accurately as “clinically studied ingredients” while containing almost nothing studied for the outcome on the front of the bottle. The phrase is true and the implication is not.
Question four: what does it cost a day?
Work out cost a day, then work out what the two or three ingredients you actually wanted would cost bought separately at published doses.
That comparison ends a lot of purchases, and it should. If a formula charges two dollars a day for eleven ingredients you cannot verify, and bacopa at 300 mg costs twenty-five cents a day with the amount printed on the bottle, the formula has to justify the difference with something other than the ingredient count.
The counter-argument, fairly put
Buying four ingredients separately means four bottles, four habits and four chances to give up. A single capsule that you actually take every day beats a perfect protocol you abandon in week three.
That is a real advantage of a combination product and it is worth money. It is not worth an unlimited amount of money, and it is not a reason to skip the first three questions.
Patterns worth walking away from
- No Supplement Facts panel anywhere on the site. The single clearest signal in the category.
- A countdown timer or a stock counter. Both are fabricated. Neither has anything to do with the product.
- An unbroken wall of five-star reviews. Genuine products have a distribution. Read the three-star ones first, if there are any.
- “Clinically proven” over an ingredient list. Ask which ingredient, in which trial, at what dose — the answer is usually that a component was studied, not the product.
- A struck-through “regular price” that is always struck through. A permanent sale is a price, not a discount.
- Pre-ticked upsells or a subscription enrolment at checkout. Information about the seller as much as about the product.
None of those is about chemistry. All of them are about whether the seller expects you to check, which turns out to be the most useful thing you can learn about a supplement company.
Applying all four to this product
| Question | CogniMary | Verdict |
|---|---|---|
| Is every amount published? | Four of fifteen are | Partial |
| Does the amount match the research? | Six of eleven blend ingredients cannot reach it; two comfortably can | Mostly no |
| Is it studied for what you want? | Ginkgo, bacopa, theanine and GPC choline yes; berberine, cinnamon, lutein and zeaxanthin not for cognition | Mixed |
| What does it cost a day? | No price was published to this site | Unknown |
Scroll this table sideways →
That is our own product, scored on our own guide, and it does not come out of it cleanly. Publishing the guide and then quietly not applying it would have been the easier choice and a worse one.
Order CogniMary from the official website
Sixty capsules, thirty days, and a panel you can read before you buy. Start with one bottle so you can see the price and the guarantee term before you commit to six.
No price was published to this website. The figure is on the checkout page.
References
The sources behind the numbers on this page.
- Snitz, O'Meara, Carlson et al. — 2009Ginkgo biloba for Preventing Cognitive Decline in Older Adults: A Randomized Trial — JAMA · PMID 20040554 · source
- Kongkeaw, Dilokthornsakul, Thanarangsarit et al. — 2014Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract — Journal of Ethnopharmacology · PMID 24252493 · source
- Lee, Kim, Park et al. — 2024Efficacy and safety of choline alphoscerate for amnestic mild cognitive impairment: a randomized double-blind placebo-controlled trial — BMC Geriatrics · PMID 39300341 · source
- Higashiyama, Htay, Ozeki et al. — 2011Effects of l-theanine on attention and reaction time response — Journal of Functional Foods · DOI 10.1016/j.jff.2011.03.009 · source
- Klugman, Sauer, Tabet & Howard — 2004Alpha lipoic acid for dementia — Cochrane Database of Systematic Reviews · CD004244.pub2 · source
- Chew, Clemons, Agrón et al. — 2015Effect of Omega-3 Fatty Acids, Lutein/Zeaxanthin, or Other Nutrient Supplementation on Cognitive Function: The AREDS2 Randomized Clinical Trial — JAMA · PMID 26305649 · source
- Alzheimer's Drug Discovery FoundationBerberine — Cognitive Vitality For Researchers — alzdiscovery.org · source
- Ranasinghe et al. — 2025Effects of Cinnamomum zeylanicum extract on lipid profile, glucose levels and its safety in adults: a randomized, double-blind, controlled trial — PLOS ONE · DOI 10.1371/journal.pone.0317904 · source
- U.S. Government Publishing Office21 CFR 101.36 — Nutrition labeling of dietary supplements — eCFR.gov · source
The question that comes after all four
Suppose a product passes all four questions: every amount published, every amount matching a researched dose, every ingredient studied for the outcome you want, at a reasonable cost a day. There is still one question left.
Is this the largest change available to you? For cognitive function, the interventions with the strongest evidence are sleep, blood pressure control, hearing correction, physical activity and social contact. None of them is sold in a bottle and all of them outperform anything in this category.
A supplement can be a reasonable addition to those. It is a poor substitute for any of them, and a product page that never says so is not being straight with you.