Eggs vs Choline Capsules: One Egg Outdoes the Standard Capsule

It is 7:40 in the morning. There are eggs in the fridge and a pan somewhere under the counter, and there is no version of the next twenty minutes in which you use either. What you do have is a bottle. One capsule, water, out the door. Behind that decision sits an assumption most people never examine: that the capsule is the concentrated version of the food, and the food is the slow, dilute way of getting the same thing.

I went looking for the number behind that assumption, expecting a judgment call about absorption curves. What I found first was arithmetic, and it runs the other way.

One note on why a publication for people who work with their heads is writing about breakfast. It is not because choline will fix your afternoon. On that question the evidence in healthy adults is close to silent, and there is a section below that says so at the length it deserves. This is a purchasing question — what is in the capsule, relative to what is in the pan — and that one has an answer.

The number on the front of the bottle is not the number you are buying

Alpha-GPC — L-alpha-glycerylphosphorylcholine — has a molecular weight of 257.22. The choline cation inside it weighs 104.17. Divide one by the other and 40.5% of the mass of alpha-GPC is choline. The other 59.5% is a glycerophosphate backbone, and that backbone is neither filler nor inert; it is the reason the two forms may not carry the same risk, which is the subject of the companion piece rather than this one.

Run the same division across the shelf. Citicoline as the free acid weighs 488.32, so it is 21.3% choline; as the sodium salt actually sold, 510.31, it is 20.4%. Choline bitartrate, 253.25, is 41.1%.

Those citicoline numbers are worth sitting with, because essentially every comparison page in this category states that citicoline is 18% or 18.5% choline by weight. Landing on 18.5% would need a molecular weight around 563, which corresponds to no standard form we could identify. The origin is not chemistry at all, and it is traceable to a specific paper.

Those same pages give alpha-GPC as 40% choline by weight, and the most cited of them adds a second figure: at equal choline content, alpha-GPC needs 46% of the dose of CDP-choline. The 46% traces to a 2013 rat study of brain monoamine transporters, and in that study it is not a finding at all — it is two numbers in the methods. The animals were given CDP-choline at 325 mg/kg/day and alpha-GPC at 150 mg/kg/day for seven days, doses the investigators describe as choline-equivalent. Divide: 150 ÷ 325 = 46%. Multiply by the rounded 40% and you get 18.4%.

So the category’s chemical constant is a pair of doses researchers chose for a seven-day rat experiment. It is an input, not a measurement. The abstract and the pages we could read carry no derivation for the equivalence, and the same two doses appear in the group’s earlier papers, so the ratio predates the study it is cited to. Run it backwards against that 40% and it implies citicoline is about 18.4% choline — the figure at issue. The chain loops rather than ending. Molecular weight, which anyone can check, says 21.3% or 20.4%. Note the direction of the error, because it is the interesting part: it makes citicoline look like a worse choline source than it is, so whatever this is, it is not marketing spin. It is what happens when a number is copied rather than checked — which, in a category where affiliate pages outrank everything, is the default.

One large hard-boiled egg contains 147 mg of choline — the figure the NIH Office of Dietary Supplements publishes, and the one every downstream page ultimately traces back to. The USDA record behind it gives 294 mg per 100 g and offers “1 large (50 g)” as a serving, which is where the halving comes from. Both were confirmed at the record. One caveat belongs with it: the entry sits in SR Legacy, a dataset the USDA froze in 2018 and marks as never to be updated again.

The most common retail unit in this category is a 300 mg alpha-GPC capsule. It delivers 121.5 mg of choline. One egg delivers 147 mg. That is the whole comparison, and you can check it on any bottle in thirty seconds with the number printed on the front. You cannot run it in the other direction, because the FDA does not require a food label to declare choline unless choline has been added. Since 2001 a product that clears the threshold may claim to be a good source of it — which is why the carton usually says nothing and the bottle says a great deal.

Three eggs come to 441 mg. Matching that from alpha-GPC takes 1,089 mg — nearly four of the standard capsules — or about 2,067 mg of citicoline. Against the reference intakes set in 1998 and still in use, three eggs is 104% of the 425 mg adequate intake for women and 80% of the 550 mg for men.

Which of the two capsules is the better buy on any axis other than choline content is a separate question, and one we have taken apart separately. This piece is only the arithmetic against food.

The headline claim is about the standard capsule, and “standard” is load-bearing. A 1,200 mg/day alpha-GPC regimen — the dose used in the clinical trials, prescribed as a drug in Korea and reportedly a prescription medicine in some European countries — delivers 486 mg and beats three eggs. Nothing sold as a single retail serving comes close.

One aside, since we are in the business of checking numbers: the USDA’s two choline datasets disagree about an egg by 28% — FoodData Central’s 294 mg per 100 g against the 2008 choline database’s 230. We use the FoodData Central figure because it is what ODS reproduces and what a reader will find. On the lower one the capsule wins the single-serving comparison by about six milligrams and the headline of this piece would not survive. The three-egg arithmetic survives either way, which is why the comparison worth repeating is the one about three.

One product-level thing follows from all this. The milligram figure on the front of the bottle does not refer to the same thing from one product to the next. On a single retailer’s shelf, as of early September 2026, you can find alpha-GPC sold as “600mg, 120 Capsules, 300mg Per Capsule” — where 600 is the two-capsule serving — next to bottles where 300 mg is the capsule and others where 300 mg is the serving. None of those labels is wrong. They are simply not comparable, and the arithmetic above only works once you know which unit you are holding. A 600 mg serving of pure alpha-GPC delivers 243 mg of choline; a 300 mg capsule delivers 121.5. Read the Supplement Facts panel, not the product title.

An egg is not a dilute capsule. It is a different compound

This is the part that changed how I think about the topic, and it is not the mass arithmetic.

That 2008 database is the only source that breaks the total down by chemical form, which is why it is worth reading even where its totals are the weaker number. Its analyses were run by mass spectrometry at the University of North Carolina, and — stated plainly, because we ask the same of everyone else — the work was supported in part by the National Cattlemen’s Beef Association and the National Pork Board alongside USDA and NIH grants.

In a hard-boiled egg, 210 of the 230 mg is phosphatidylcholine: 91% of the total, bound into a phospholipid. Free choline comes to 0.7 mg per 100 g. Glycerophosphocholine — the molecule sold in the bottle as alpha-GPC — comes to 0.5 mg per 100 g. A single 300 mg capsule contains roughly 240 times as much of that molecule as 100 g of egg does — the database counts the choline inside each compound, so the comparison is the capsule’s 121.5 mg against the egg’s 0.5 mg. The 2003 analysis the database grew out of puts eggs at 0.60 mg per 100 g — the same laboratory at an earlier stage, not an independent check.

So these are not a concentrate and a dilution of each other. They are different compounds that share a fragment. A food that genuinely is a dilute version of the capsule does exist, and it is not eggs: the USDA choline database puts braised beef liver at 83 mg of glycerophosphocholine per 100 g, so a 3 oz serving carries about 71 mg — more than half of what a 300 mg capsule delivers of the actual molecule. Wheat germ, oat bran and Atlantic cod carry the most of it after liver, all around 30 mg per 100 g; pork and dairy carry a little. The two USDA-linked datasets disagree about salmon by a factor of seven — 41 mg per 100 g against under 6 — and on the higher figure it would outrank all three. We could not resolve which is right. The 2003 paper carries a published correction that we were unable to obtain, so it is possible this was fixed twenty-three years ago and the fix never reached the database.

Two smaller facts fall out of the same table. Raw egg white is 1.1 mg per 100 g against the raw yolk’s 680 — an omelette made of whites alone is barely on this map. Order them for the protein if you like; they are not a choline food. The yolk is the densest common food in the database after liver.

One more wrinkle: most supplemental alpha-GPC is made enzymatically from egg or soy lecithin, which is why it is classed as a semisynthetic derivative of lecithin rather than as an extract. The capsule is frequently manufactured out of the food it is being compared against.

Does the form change what actually arrives?

Probably, in most people — and this is exactly where a food-first argument becomes easy to oversell, so here is all of it. Three randomised crossover trials have put an egg-derived form against choline bitartrate at matched choline doses. Two favoured the food, one did not. Here is all three.

The first gave 18 Dutch adults a drink containing 3 g of choline, either as freeze-dried egg-yolk phospholipids or as choline bitartrate. Plasma choline response over six hours was more than three times larger after the phospholipid drink: iAUC 8,020 ± 2,967 versus 2,424 ± 1,112 µmol/L·min, p < 0.01. Five things sit next to that number. The participants averaged 62.3 years old, four decades above this site’s reader, in a paper whose title says “healthy adults.” The 3 g dose is many times a normal intake, and the authors cannot rule out that it saturated the transport pathway carrying the salt form. The study’s second hypothesis — that phospholipid-bound DHA would also absorb better — failed outright (p = 0.63). And its funding statement says the research received no external funding, while its conflict-of-interest statement says two authors are employed by AAK Netherlands BV, which funded the study and makes the ingredient that won. We cite it because it supports our argument, which is when a disclosure matters most. And the only adverse-event data we retrieved in this comparison run against the food: seven recorded changes in faecal consistency, four of them after the egg-phospholipid drink against one after the control, a difference the authors note themselves.

The second trial is the closest population match in this literature. Thirty adults averaging 25.6 years old ate either three eggs a day or took choline bitartrate, both around 400 mg of choline daily, for four weeks each. Fasting plasma choline rose 20% on eggs (p = 0.023). On the supplement it did not rise significantly at all — a null that is the mirror image of the headline and belongs in the same sentence as it. Funded by the Egg Nutrition Center, the research arm of the American Egg Board, with partial funding from Brazil’s CNPq. Industry money pointing at a pro-food result is still industry money.

And the trial that did not replicate it, reported by the same laboratory as a conference abstract rather than a full paper: 23 adults with metabolic syndrome, aged 32 to 70, randomised to three eggs a day or the supplement at the same 400 mg of choline, four weeks each. Plasma choline went from 7.9 nmol/mL at baseline to 9.9 on eggs and 9.5 on the supplement — both significant against baseline, neither significantly different from the other. TMAO did not move at any point. So the supplement worked in this population. That makes the result a mirror of the young-adult trial rather than a repeat of it: what changed was not that food stopped winning but that the salt started working, and nobody has explained why. Egg Nutrition Center funded, stated at source. Two trials favour food, one finds no difference, and nobody has explained the gap.

One more human study compares the forms directly, and it is the smallest of them. Six healthy men took the same choline dose in four labelled forms, six weeks apart, with plasma followed for a week. The egg form moved choline into the blood latest and gave no advantage in total exposure — and, the part that matters for the last section of this piece, almost none of the labelled TMAO that the capsule forms produced. Six men, one dose each, and we read the abstract rather than the paper. ODS, for its part, states that no studies have compared the relative bioavailability of choline across the different supplement forms. That tracer study is the closest thing to an exception, and it is six men.

On the capsule side of the comparison there is exactly one human time course we could retrieve at all, and it is small: eight healthy men, mean age 25, given 1,000 mg of alpha-GPC or placebo in a double-blind crossover. Plasma free choline rose 38% to 51% above baseline and was still up at the last measurement. That measurement is at 120 minutes, because the study drew blood at baseline, 60 and 120 minutes and stopped. Blood glucose did not change — a null the study reports and the supplement pages citing it do not.

Which matters, because the pharmacokinetic figures for alpha-GPC and citicoline that circulate on comparison pages — the “4 to 6 hours,” the “60 to 70 hours” — we could not trace to a primary paper. The four-hour figure is sometimes attributed to the trial above; its abstract and index record carry no four-hour measurement, and the attribution appears in later writers rather than in the study’s own stated design. We do not repeat numbers whose origin we cannot name.

Where “90% of Americans don’t get enough choline” comes from

It comes from somewhere real, which is the first surprise. NHANES intakes compared against the adequate intake give roughly that: the Linus Pauling Institute reports only 6% of women and 11% of men above the AI. Mean intake is about 402 mg a day for men and 278 mg for women in the 2013–2014 cycle ODS cites, 390 mg and 284 mg in the 2015–2018 cycle LPI cites — different survey years, not a contradiction.

The second surprise is that the 2018 Nutrition Today review that popularised the figure says, in the same passage, that it cannot mean what it is used to mean. An adequate intake, unlike an estimated average requirement, cannot be used to estimate the prevalence of inadequacy in a population. Two independent NHANES analyses say the same thing explicitly and report only the percentage above the AI for that reason. There is no EAR for choline. Without one, the share of the population with genuinely inadequate intakes cannot be calculated.

Then look at where the reference value came from. The adult male AI was informed by a depletion–repletion study in adult men who developed signs of liver damage on a deficient diet; the reviewers who popularised the 90% figure describe it that way; the abstract we read does not name the study. A later depletion–repletion study of the same design gives the most concrete published numbers: 57 adults fed under 50 mg of choline per 70 kg of body weight per day — under a tenth of the AI — for up to 42 days, of whom 37 developed liver dysfunction, resolving in 29 when they were refed at a quarter to three-quarters of the AI. That is real evidence that dietary choline is required. It is evidence about near-total deprivation, and the endpoint was a liver enzyme. The AIs for women and other life stages were scaled from the men’s figure by standard reference body weights rather than measured.

So a number derived from liver damage under near-total deprivation, body-weight-scaled to everyone else, explicitly not built to count deficiency, is now the basis on which a 30-year-old developer is told he is deficient. The honest version: about 90% of Americans eat less choline than the reference intake. ODS supplies the other half in one sentence — frank choline deficiency in healthy men and non-pregnant women is very rare — which sits a few paragraphs from the 90% statistic in the same document and almost never travels with it.

One more piece of context. ODS notes that supplements contribute very little to total choline intake, that typical doses run from 10 to 250 mg, and that the forms used are bitartrate, phosphatidylcholine and lecithin. Alpha-GPC and citicoline are not listed in its supplement section at all.

What more choline does for a working day

Here is the part the arithmetic cannot rescue.

The largest review of the field searched six databases to July 2014 and identified 50 relevant articles. Its conclusion, in the authors’ framing as reported in the abstract: choline may have beneficial effects on cognition in adults, but high-quality intervention studies are lacking; results on body composition, lipids and cardiovascular health were inconsistent; and possible harmful effects on cardiometabolic health need careful evaluation. We read the abstract, not the full text, and say nothing about what the rest contains.

That is a statement about the quality of the evidence rather than a null result — arguably worse for the supplement, because it is the reviewers’ own hedge. It is also not what the NIH fact sheet says it says: ODS renders the same review as 13 studies finding that choline supplements did not produce clear improvements in cognition in healthy adults. Different number of studies, different shape of conclusion. A claim moving one citation step and arriving in a different shape is the most common failure in nutrition writing, and it happens inside careful documents too — the same failure mode we unpack in why cognitive trials find nothing.

The one trial everyone points to, read properly

A placebo-controlled trial in healthy people does exist, and it is the one the category cites. Twenty-eight students, mean age 19.5, drank 2 g of choline bitartrate dissolved in orange juice — 800 mg of choline, which the authors themselves describe as roughly five hard-boiled eggs’ worth — or a placebo, in two sessions a week apart. Seventy minutes later they did a computer aiming task.

They hit closer to the centre of the target (p = 0.030). They were also slower (p = 0.009). And the task’s own composite score, the one combining speed and accuracy, did not move: 3,750 against 3,813, p = 0.656. The authors’ reading is that choline shifted the speed–accuracy trade-off toward accuracy, not that it improved performance. The paper is titled “Improved human visuomotor performance.” Both statements are true. Only one of them is what a reader takes from the title, and it is not the one the evidence supports.

One more thing, and it is in the methods rather than the results: the participants also did a spatial working-memory task in the same sessions. The paper says those results were inconclusive and does not present them. Funded by a Dutch research council grant, no competing interests declared.

What is not in dispute:

• Nobody has tested whether raising choline intake changes cognitive performance in healthy working-age adults doing anything resembling real work. The trial above is a mouse-cursor task in teenagers.
• The positive human results for alpha-GPC sit in Alzheimer’s disease, vascular cognitive impairment and stroke recovery, at 1,200 mg a day for six months in the main Alzheimer’s trial, which we did not open and which sources describe with differing participant counts — a population and a dose that have nothing to do with a 300 mg capsule bought for a Tuesday afternoon.
• A Cochrane review of 12 randomised trials of lecithin found no clear clinical benefit in Alzheimer’s disease or Parkinsonian dementia. The supporting observational signals — 1,391 Framingham Offspring adults aged 36 to 83, 2,195 Norwegians aged 70 to 74 — are observational work, one a prospective cohort scored from food-frequency questionnaires, the other a plasma measurement, in populations decades older than this one.
• The Alzheimer’s Drug Discovery Foundation, reviewing citicoline, states there is no evidence that supplementation beats adequate dietary choline for long-term brain health, and that the absence of negative studies in the literature suggests some publication bias. We read an excerpt of that document, not all of it.

So the accurate sentence is the unsatisfying one. Three eggs deliver more choline than a capsule. Whether more choline does anything for your Tuesday afternoon has not been shown in people like you, in either direction.

What to do on Monday

Read the label for the choline number, not the compound number. Multiply alpha-GPC by 0.405 and citicoline by roughly 0.21. If a bottle gives only the compound mass, you can now convert it — and if the panel is ambiguous about whether that figure is blend mass or active mass, treat the ambiguity as information about the product.

If the goal is the reference intake, breakfast gets most of the way there and the capsule doesn’t. Three whole eggs is 441 mg — 104% of the 425 mg reference for women, 80% of the 550 mg for men, and more than any single serving sold in this category short of a pharmaceutical regimen. Whole eggs: the whites carry about 1 mg per 100 g. In July 2026 the US average retail price was $2.189 a dozen, so three eggs ran about 55 cents against roughly 50 cents for a 600 mg alpha-GPC serving delivering 243 mg — about 12 cents per 100 mg of choline from eggs against 21 from the capsule. But eggs touched $6.23 a dozen in March 2025, which reverses that entirely. Do not decide this on price.

If you specifically want alpha-GPC from food, the food is liver. Roughly 66 to 71 mg in a 3 oz serving, with wheat germ and oat bran carrying a useful amount, and eggs essentially none. The same serving of liver also carries 356 mg of choline — more than any single serving sold in this category, and the one line in this piece that inverts the purchase rather than just cancelling it.

And know what you have not bought. More choline, from either source, has not been shown to improve cognition in healthy adults of working age. If the afternoon is the actual problem, that is a different question from this one — and it is a question about sleep and timing rather than about what to swallow.

The line worth keeping is the one that took a database to find. A 300 mg alpha-GPC capsule holds about 240 times as much glycerophosphocholine as 100 g of egg — and the egg still holds more choline. The capsule is not a concentrated egg. It is a different molecule, and the only common food that is genuinely a dilute version of it is one almost nobody in this conversation is eating.

What this piece has not answered

Two things, and both are real.

The first is whether the form changes what your gut bacteria do with the choline. Some of it becomes trimethylamine, which your liver turns into TMAO, a metabolite associated with cardiovascular events. The tracer study above, in six men, suggests the egg form produces markedly less of it than the capsule forms; an older human egg challenge points the other way; nobody has reconciled them. I spent longer on that than on anything else here and it does not resolve.

The second is that alpha-GPC carries a stroke signal from a Korean cohort of twelve million people — and a second Korean cohort, of half a million people with mild cognitive impairment, in which alpha-GPC use was not associated with more stroke. Neither is about a healthy thirty-year-old taking 300 mg from a bottle, and saying so takes more than a paragraph. Both questions have their own article: what the Korean cohorts actually show.

Nothing in either changes the arithmetic above. They change how confident you should be about the capsule, which is a different question from whether it contains what you think it does.

About this article

Written by Leah Elish. Leah covers food-first nutrition — what a nutrient does, how much of it is in a meal, and what the capsule adds to that. Not a dietitian or clinician — traces nutritional claims back to the studies that supposedly support them.

Medical review: None. NeuriFuel does not currently have a licensed clinician on the editorial team, and this article has not been medically reviewed. We state this rather than implying an authority we do not have. See our About page for our full methodology.

Sources: 21 numbered sources. Two of the entries bundle more than one paper, so 23 individual works are referenced. Among the 21: six human randomised or placebo-controlled trials, one controlled human feeding study, two systematic reviews, one animal study, one food-composition analysis, and two US government nutrient datasets. The rest are observational cohorts, authority and institutional documents, a government price series, and records cited only for identification. Funding disclosures could not be retrieved for several of the studies cited; where they are absent here, that means we could not find them, not that they were clean. Where a value could not be retrieved it is marked in the text rather than estimated, and where sources conflict — the two USDA egg figures, the two NHANES intake cycles, the two conclusions drawn from the same 2015 review — both are given.

Corrections: Found an error? Write to hello@neurifuel.com with a source and we will fix it and log the correction.

Last updated: 5 September 2026

References

1. Patterson KY, Bhagwat SA, Williams JR, Howe JC, Holden JM. USDA Database for the Choline Content of Common Foods, Release Two. Agricultural Research Service, USDA, January 2008. Supported in part by the National Cattlemen’s Beef Association and the National Pork Board, alongside USDA and NIH grants. Read in full.
2. National Institutes of Health, Office of Dietary Supplements. Choline — Fact Sheet for Health Professionals. Updated 2 June 2022. Read in full.
3. USDA FoodData Central, “Egg, whole, cooked, hard-boiled,” FDC ID 173424, NDB 1129, https://fdc.nal.usda.gov/food-details/173424/nutrients — choline 294 mg per 100 g. Data type SR Legacy, published 1 April 2019; portion options include 1 large (50 g). The USDA marks SR Legacy as a final release that will not be updated. Opened at source 30 August 2026; portion options and the SR Legacy notice read 3 September 2026. Earlier drafts cited FDC ID 172128, an identifier taken from an aggregator that does not resolve to this food; the value was unaffected.
4. Smolders L, de Wit NJW, Balvers MGJ, Obeid R, Vissers MMM, Esser D. “Natural Choline from Egg Yolk Phospholipids Is More Efficiently Absorbed Compared with Choline Bitartrate.” Nutrients 2019;11(11):2758. DOI 10.3390/nu11112758 · PMID 31766273. Funded by AAK Netherlands BV, manufacturer of the tested ingredient; two authors employed by the funder. The paper’s funding and conflict statements contradict each other. Read in full.
5. Lemos BS, Medina-Vera I, Malysheva OV, Caudill MA, Fernandez ML. “Effects of Egg Consumption and Choline Supplementation on Plasma Choline and Trimethylamine-N-Oxide in a Young Population.” J Am Coll Nutr 2018;37(8):716–723. DOI 10.1080/07315724.2018.1466213 · PMID 29764315. Funded by the Egg Nutrition Center, research arm of the American Egg Board, and by CNPq. Read at abstract level.
6. Conference abstract, not a full paper. Thomas MS, DiBella M, Malysheva OV, Caudill MA, Blesso C, Fernandez ML. “Intake of 3 Eggs/Day or Equivalent Amount of Choline as Supplement for 4 Weeks Increases Plasma Choline Without Changing Plasma TMAO in Participants with Metabolic Syndrome.” Current Developments in Nutrition; PMC7258582. Funded by the Egg Nutrition Center, stated on the record itself. Published in an American Society for Nutrition supplement in the Objectives–Methods–Results–Conclusions format; the record carries no full text beyond the abstract, which is what we read. Volume and pagination not retrieved.
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13. Linus Pauling Institute, Micronutrient Information Center, Choline. Oregon State University. Positions taken from the page; the register records no reading level for it.
14. Zeisel SH, Mar M-H, Howe JC, Holden JM. “Concentrations of choline-containing compounds and betaine in common foods.” J Nutr 2003;133(5):1302–1307. PMID 12730414. Abstract read at PubMed. Erratum in J Nutr 2003;133(9):2918 — cited elsewhere as 2918–9, and the record and the citing literature disagree about whether it runs to one page or two. We could not obtain the correction itself through any route available to us, so we cannot say which values it changes. The analytical work behind the USDA choline database and the source of the alpha-GPC-by-food values.
15. Tayebati SK, Tomassoni D, Nwankwo IE, Di Stefano A, Sozio P, Cerasa LS, Amenta F. “Modulation of monoaminergic transporters by choline-containing phospholipids in rat brain.” CNS Neurol Disord Drug Targets 2013;12(1):94–103. DOI 10.2174/1871527311312010015 · PMID 23244432. Rat study; the source of the 46% dose ratio. Read at abstract level plus extracted methods and figure text; funding not retrieved.
16. Alzheimer’s Drug Discovery Foundation, Cognitive Vitality report on citicoline, updated 30 November 2023. An excerpt was read, not the full document.
17. US Bureau of Labor Statistics, series APU0000708111, eggs grade A large, US city average. July 2026 value $2.189 per dozen; March 2025 peak $6.227. Series table read directly at data.bls.gov on 3 September 2026. The August 2026 cell was still empty at that date.
18. Naber M, Hommel B, Colzato LS. “Improved human visuomotor performance and pupil constriction after choline supplementation in a placebo-controlled double-blind study.” Sci Rep 2015;5:13188. DOI 10.1038/srep13188 · PMID 26271904 · PMC4536529. Funded by the Netherlands Organization of Scientific Research, Vidi grant 452-12-001; authors declare no competing financial interests. Read in full.
19. Kawamura T, Okubo T, Sato K, Fujita S, Goto K, Hamaoka T, Iemitsu M. “Glycerophosphocholine enhances growth hormone secretion and fat oxidation in young adults.” Nutrition 2012;28(11–12):1122–1126. DOI 10.1016/j.nut.2012.02.011 · PMID 22673596. Indexed as non-US government research support; specific funders not retrieved. Read at abstract level plus one extracted results paragraph.
20. Two NHANES supplement-contribution analyses, PMC5748775 and PMC5793232, cited for their statement that the prevalence of inadequate choline intake cannot be determined in the absence of an estimated average requirement. Read at secondary level; titles and authors not retrieved.
21. De Jesus Moreno Moreno M. Clin Ther 2003;25(1):178–193. PMID 12637119. Read at secondary level; the primary paper was not opened, and sources disagree about its participant count.