Choosing a memory supplement
This is written by a retailer, applied to its own product, and it reaches an inconvenient answer. That is the test of a method: it has to be allowed to.
Question one: is there a dose
Can you find out how many milligrams of each active ingredient are in a serving? If not, you cannot compare the product with anything, including a cheaper version of itself.
This question eliminates a large fraction of the category on its own. A proprietary blend with a total and an ingredient list is compliant and it is not comparable: you can derive ceilings, which is useful, but you cannot derive doses.
The answer for Cognizil is no. One of twenty-two dietary ingredients carries a figure. Twenty-one share 15.47 mg and the split is not published.
A product that fails question one is not necessarily bad. It is necessarily unassessable, and those are different criticisms. What you can do with a blend is check the ceilings, which is question two.
Question two: does the ceiling reach the literature
Descending order gives you an upper bound for every position. Compare that bound against the lowest dose used in the published research for that ingredient.
- Look up the ingredient's studied dose. Use the bottom of the range, not the middle, because you are testing the most favourable case.
- Compute the ceiling: blend total divided by the ingredient's position.
- If the label declares an extract ratio, multiply the ceiling by it. Grant the manufacturer's own number in full.
- Compare. If the best case is below the lowest studied dose, that ingredient cannot be doing what it is on the label for.
- Repeat for the ingredients you actually care about. Three is usually enough to settle it.
On this label, fourteen of the sixteen ingredients with a verifiable researched dose fail that test, by factors from 1.45× to 6,787×. Two pass. That is the answer the method produces here and we publish it.
Question three: what is the evidence for the ingredient at all
A correct dose of something with no evidence is still nothing. It is worth checking the ingredient before checking the milligrams.
| Level | What it is | How much weight |
|---|---|---|
| Systematic review or meta-analysis of human trials | Many trials, pooled and assessed | The most, when the trials are decent |
| Randomised controlled trials in humans | The individual studies | Substantial, especially if replicated |
| Single small trial | One study, often industry-funded | Some, and treat a single positive result cautiously |
| Animal or cell studies | Mice, or cells in a dish | Mechanistic interest only. Not a human finding |
| Traditional use | Long historical use | A reason to investigate, not a result |
| Nothing | No human trial exists | None |
Scroll this table sideways →
The bottom row is not hypothetical. One ingredient on this label — raspberry ketones — has no human trial at supplement doses at all, which the US Olympic and Paralympic Committee's own factsheet states plainly.
Questions that feel useful and are not
- How many ingredients does it have? More ingredients in a fixed total means less of each. Ingredient count is an argument against a formula, not for it.
- Is it natural? Undefined, and irrelevant to whether it works.
- Does it have a GMP seal? Useful, but it certifies a facility, not a formula.
- What do the reviews say? The weakest evidence available in this category, and the easiest to manufacture.
- Is it a liquid? Format affects absorption for some molecules and adherence for most people. It does not create dose.
- Is it expensive? Price carries almost no information about content in this category.
Every one of those six appears on product pages as a selling point, including on sites like this one. None of them survives question one.
What to do instead
- Pick the one or two ingredients with the best human evidence for what you actually want.
- Buy them individually, at a disclosed dose, standardised where standardisation exists.
- Compare the cost per researched dose rather than per bottle.
- Run one change at a time for the length of the trials, usually eight to twelve weeks.
- Write down a baseline before you start, and read your notes rather than your memory at the end.
- Before any of the above, deal with sleep, hearing, blood pressure and medication review. Every one of them has a larger evidence base for cognition than anything in this category.
That last point is the honest one and it is why it is last rather than buried. A retailer's site is an odd place to read it, and it is still true.
This label, measured →Who this product suits →The ingredient list →
See the Cognizil packs
Two, three or six bottles, priced plainly, with a 180-day window on the sales page kits. Read the best case first, then decide.
Shipping is calculated at checkout. This site publishes no figure it was not given.
References
Every source below was opened and read. Nothing here cites a study we did not read, and no identifier on this site was written from memory.
- U.S. Government Publishing Office21 CFR 101.36 — Nutrition labeling of dietary supplements — eCFR.gov · source
- U.S. Food and Drug AdministrationDietary Supplement Labeling Guide: Chapter IV, Nutrition Labeling — FDA.gov · source
- U.S. Food and Drug AdministrationDaily Value and Percent Daily Value: Changes on the New Nutrition and Supplement Facts Labels — FDA.gov · source
- U.S. Food and Drug AdministrationGrapefruit Juice and Some Drugs Don’t Mix — FDA.gov · source
- U.S. Food and Drug AdministrationFDA Calls on Certain Firms to Stop Producing and Issuing Misleading ‘FDA Registration Certificates’ — FDA.gov · source
- Booker, Frommenwiler, Reich et al. — 2022Understanding plant to extract ratios in botanical extracts — Frontiers in Pharmacology · DOI 10.3389/fphar.2022.981978 · source
- Shin, Lee, Yang, Lim & Ernst — 2010Maca (L. meyenii) for improving sexual function: a systematic review — BMC Complementary and Alternative Medicine · PMID 20691074 · source
- Ngondi, Etoundi, Nyangono et al. — 2009IGOB131, a novel seed extract of the West African plant Irvingia gabonensis, significantly reduces body weight and improves metabolic parameters in overweight humans — Lipids in Health and Disease · PMID 19254366 · source
- Centre for Reviews and DisseminationThe efficacy of Irvingia gabonensis supplementation in the management of overweight and obesity: a systematic review of randomized controlled trials — NCBI Bookshelf (DARE) · NBK132337 · source
- Zhang, Liu, Li et al. — 2016The impact of grape seed extract treatment on blood pressure changes: a meta-analysis of 16 randomized controlled trials — Medicine (Baltimore) · PMID 27537554 · source
- Congretel, Bonnet, Gaudel et al. — 2023Effect of Guarana (Paullinia cupana) on Cognitive Performance: A Systematic Review and Meta-Analysis — Nutrients · PMID 36678305 · source
- European Medicines Agency, Committee on Herbal Medicinal ProductsAssessment report on Eleutherococcus senticosus (Rupr. et Maxim.) Maxim., radix — ema.europa.eu · source
- Schaffler, Wolf & Burkart — 2013No benefit adding Eleutherococcus senticosus to stress management training in stress-related fatigue/weakness, impaired work or concentration — Pharmacopsychiatry · PMID 23740477 · source
- Pop, Cherecheș, Buzoianu et al. — 2021Standardized astragalus extract for attenuation of the immunosuppression induced by strenuous physical exercise: randomized controlled trial — Journal of the International Society of Sports Nutrition · PMID 34271953 · source
- Zhang, Lin, Xu, Leung & Chan — 2014Astragalus (a traditional Chinese medicine) for treating chronic kidney disease — Cochrane Database of Systematic Reviews · CD008369.pub2 · source
- European Food Safety Authority — 2018Scientific opinion on the safety of green tea catechins — EFSA Journal · DOI 10.2903/j.efsa.2018.5239 · source
- National Institute of Diabetes and Digestive and Kidney DiseasesGymnema, in LiverTox: Clinical and Research Information on Drug-Induced Liver Injury — NCBI Bookshelf · NBK610217 · source
- Godard, Johnson & Richmond — 2005Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men — Obesity Research · PMID 16129715 · source
- Henderson, Magu, Rasmussen et al. — 2005Effects of Coleus forskohlii supplementation on body composition and hematological profiles in mildly overweight women — Journal of the International Society of Sports Nutrition · PMID 18500958 · source
- Zsiborás, Matics, Hegedűs et al. — 2023The effects of capsaicin intake on weight loss among overweight and obese subjects: a systematic review and meta-analysis of randomised controlled trials — British Journal of Nutrition · PMID 36938807 · source
- Takeoka, Dao, Wong, Lundin & Mahoney — 2001Identification of benzethonium chloride in commercial grapefruit seed extracts — Journal of Agricultural and Food Chemistry · PMID 11453769 · source
- Avula, Dentali & Khan — 2007Simultaneous identification and quantification by liquid chromatography of benzethonium chloride, methyl paraben and triclosan in commercial products labeled as grapefruit seed extract — Die Pharmazie · PMID 17867553 · source
- Zeng, Li, Wang et al. — 2024Effects of Ginseng on Cognitive Function: A Systematic Review and Meta-Analysis — Phytotherapy Research · PMID 39474788 · source
- Operational Supplement Safety, Consortium for Health and Military PerformanceRaspberry ketone dietary supplements for weight loss — opss.org · source
- Gleeson — 2008Dosing and efficacy of glutamine supplementation in human exercise and sport training — Journal of Nutrition · PMID 18806122 · source
- Deijen & Orlebeke — 1994Effect of tyrosine on cognitive function and blood pressure under stress — Brain Research Bulletin · PMID 8293316 · source
- McNeal, Meininger, Wilborn et al. — 2018Safety of dietary supplementation with arginine in adult humans — Amino Acids · PMID 29858688 · source
- Collier, Casey & Kanaley — 2005Growth hormone responses to varying doses of oral arginine — Growth Hormone & IGF Research · PMID 15809017 · source
- Trexler, Smith-Ryan, Stout et al. — 2015International Society of Sports Nutrition position stand: Beta-Alanine — Journal of the International Society of Sports Nutrition · PMID 26175657 · source
- Joint FAO/WHO Expert Committee on Food AdditivesGlycyrrhizinic acid — evaluation and intake guidance — WHO JECFA database · source
- Hepsomali, Groeger, Nishihira & Scholey — 2020Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic review — Frontiers in Neuroscience · DOI 10.3389/fnins.2020.00923 · source
- Sutanto, Loh, Kim & Kim — 2021The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression — Nutrition Reviews · PMID 33942088 · source
- NIH Office of Dietary SupplementsCarnitine — Health Professional Fact Sheet — ods.od.nih.gov · source
- NIH Office of Dietary SupplementsChromium — Health Professional Fact Sheet — ods.od.nih.gov · source
- U.S. Food and Drug AdministrationQuestions and Answers on Dietary Supplements — FDA.gov · source
What the evidence actually supports for cognition
A guide about choosing a supplement owes the reader a sentence about the alternatives, and this one is on a retailer's site, which makes it worth more rather than less.
| Intervention | Why it belongs above a supplement |
|---|---|
| Treating hearing loss | Hearing loss has one of the strongest observed associations with cognitive decline of any modifiable factor. |
| Sleep, and treating sleep apnoea | Apnoea is common, under-diagnosed, and directly degrades the memory consolidation that happens during sleep. |
| Blood pressure control in midlife | One of the better-supported modifiable factors in the dementia prevention literature. |
| A medication review | Anticholinergics and sedatives impair cognition measurably. A pharmacist can do this in twenty minutes. |
| Regular aerobic exercise | Consistently associated with cognitive outcomes across a large literature. |
| Treating depression | Frequently presents as a cognitive complaint, particularly in older adults, and is treatable. |
Why this table is here
Because a buyer who works through the three questions above, concludes that most of the category is unassessable, and then does nothing has spent the effort for no return. The six rows above are where the return is.
None of that is a reason not to take a supplement as well. It is a reason not to take one instead.
A short checklist you can use in a shop
- Is there a dose for the ingredient you came for? If not, put it down or derive the ceiling.
- Does the ceiling reach the bottom of the studied range? Total divided by position, times any declared extract ratio.
- Does the ingredient have human evidence at all, or only animal and traditional use?
- Is the extract standardised to a marker, or is it just a ratio?
- What is the cost per researched dose, not per bottle?
- Does it contain anything that interacts with what you already take?
Six questions. The first two eliminate most of the shelf, the third eliminates most of what survives, and the last one is the only one that has a safety consequence.
The label method →This product's ingredient list →Interactions worth raising →