Choline in real life: food, testing, supplements, and the questions that actually matter
- Richard Moore
- 2 days ago
- 12 min read
Picture the moment most of these articles are often read in. Someone has just finished the second piece in this series, the one about amyotrophic lateral sclerosis (ALS). It is late, perhaps too late, and the words from the first two articles are still circling in their head alongside a diagnosis they did not ask for, either their own or someone they love. They open a new tab, type in “best choline supplement,” and a wall of bottles appears, every one of them more confident than the science behind it.
That is the moment this article is for.
This final piece looks at what happens when the science meets real life: why one person may need more choline than another, why testing is still messy, where genetics may matter, how different supplement forms actually differ, where trimethylamine N-oxide (TMAO) complicates the picture, and how to think about all of that without drifting into either fear or wishful thinking.
In our clinic, this is often the point where a careful biological story starts to flatten into a shopping list. A nutrient becomes a promise. A sensible question about diet or physiology turns into a search for the one capsule that is supposed to make the whole thing simpler. Choline deserves better than that, and so do the people thinking seriously about it.
Why two people need very different amounts
Published intake figures look tidy on paper. Real biology rarely is.
The body does have a back-up route for making some of its own phosphatidylcholine when dietary choline runs short. That route depends on an enzyme in the liver called phosphatidylethanolamine N-methyltransferase (PEMT). How strongly that back-up system runs depends on sex, hormonal status, life stage, and inherited variation in choline-related genes, all of which differ from person to person (Zeisel, 2012; van der Veen et al., 2017; Burns et al., 2025).
That helps explain why the same plate of food can be perfectly adequate for one person and quietly insufficient for another. It also explains why broad statements about whether a population is “getting enough” can only take you so far. They are useful at population level, but they do not always tell you very much about the actual person in front of you.
Can you test choline status, and do genes matter?
This is one of the messier parts of the topic, largely because people often expect a single clean answer and there is not one.
At the moment, there is no blood test that can tell you with confidence whether the body has enough choline in all the places that matter. Obeid et al. (2023), in a scoping review conducted for the Nordic Nutrition Recommendations, concluded that there are currently no optimal biomarkers that accurately reflect choline deficiency or sufficiency in routine practice. Plasma choline and betaine can tell us something in tightly controlled research settings, but that is not the same thing as a reliable, day-to-day clinical readout of whole-body status (Obeid et al., 2023).
So in practice, thinking about choline status is usually less about reading one lab number and more about putting a pattern together. Diet matters. Appetite matters. So do liver function, kidney function, and the wider nutritional picture. That is less satisfying than a neat yes-or-no test, but it is a more honest reflection of where the science currently stands (Obeid et al., 2023).
Genetics adds another layer. The body has a back-up way of making some of its own phosphatidylcholine in the liver, through the enzyme phosphatidylethanolamine N-methyltransferase (PEMT). The strength of that back-up system is not the same in everyone. Oestrogen increases PEMT activity, which is one reason premenopausal women tend, on average, to have more metabolic protection than men or postmenopausal women when dietary intake is modest (Fischer et al., 2010; Resseguie et al., 2011).
Common genetic variants can make that back-up system less efficient. In a controlled feeding study, Fischer and colleagues found that a common PEMT variant, rs12325817, increased susceptibility to signs of choline deficiency in women on a low-choline diet, while oestrogen exposure reduced this risk in postmenopausal women (Fischer et al., 2010). In plain English, two people can eat very similar diets and still not have the same margin for error.
PEMT is not the only gene of interest. Studies and reviews have also highlighted variants in choline dehydrogenase (CHDH), methylenetetrahydrofolate dehydrogenase 1 (MTHFD1), and other genes involved in choline and folate metabolism as potential modifiers of choline need, particularly when intake is low (da Costa et al., 2006; Ganz et al., 2017). That does not mean everyone needs genetic testing for single nucleotide polymorphisms (SNPs) in choline-related genes. Most people do not. What it does mean is that “average intake” can be a poor guide for an individual person. Where genetic context is likely to be clinically useful, You Nutrition Clinic can also support with nutrigenomic testing, including Lifecode GX, as part of a broader case review rather than in isolation.
So should someone do genetic testing specifically for choline? Usually not as a first move. In practice, genetic data tend to be most useful as context rather than as a stand-alone answer. They may help explain why one person appears more vulnerable to a low-choline diet than another, but they do not replace the basics: diet history, symptoms, clinical pattern, and the wider context in which the person is eating and living. Used well, genetics can sharpen judgement. Used badly, they can create a more expensive kind of false certainty (Ganz et al., 2017).
Sorting through the supplement aisle
This is where the picture becomes less straightforward.
The first two articles in this series explain why choline is biologically important. It sits across acetylcholine signalling, membrane phospholipids, mitochondrial resilience, methylation-related chemistry, oxidative stress, and inflammatory pathways, so it is not surprising that it keeps showing up in neurodegeneration research. Where the picture becomes less straightforward is when that biological importance is treated as though it automatically translates into strong clinical evidence for supplementation. At the moment, it does not. The biology is compelling, but the human supplement evidence is much narrower and much less even than people often assume.
When people talk about “a choline supplement”, they may also be talking about several quite different compounds, which is why the label alone tells you very little.
Citicoline, also called cytidine diphosphate-choline (CDP-choline), is not simply a basic choline salt. It is involved in phosphatidylcholine synthesis and tends to come up most often in neurology and cognition research. Human reviews describe possible benefits in stroke recovery, mild cognitive impairment, dementia-related conditions, and broader neurological disorders, and a systematic review in Parkinson’s disease (PD) reported improvements in rigidity, akinesia, tremor, handwriting, and speech across the included studies. Even so, those studies were small and methodologically mixed, so the signal is better described as interesting than settled. What the evidence supports most clearly is an effect on cognition and function in selected settings, not direct proof that citicoline improves mitochondrial dysfunction, oxidative stress, calcium balance, or inflammation in neurodegenerative disease (Jasielski et al., 2020; Bonvicini et al., 2023; Que et al., 2021).
Alpha-glycerophosphocholine (alpha-GPC) is usually framed as more “brain-targeted” because it crosses the blood-brain barrier reasonably well. A 2023 systematic review and meta-analysis found that alpha-GPC, alone or combined with donepezil, improved cognition, behaviour, and functional outcomes in adult-onset neurological conditions, particularly dementia-related syndromes associated with cerebrovascular injury. That makes it easier to discuss through the lens of signalling and cognition than through claims about disease modification. Here too, the evidence does not justify saying that trials have already shown clear improvements in mitochondrial biology, calcium handling, oxidative stress, or inflammation in neurodegenerative disease (Sagaro et al., 2023).
Phosphatidylcholine makes the most immediate biological sense through the membrane story, because it is one of the major phospholipids in cell membranes and sits close to membrane integrity, mitochondrial resilience, and wider cellular stability (van der Veen et al., 2017). But that biological fit should not be confused with proven clinical effect. Oral phosphatidylcholine is largely broken down in the gut, so it acts more as a choline-and-fatty-acid delivery system than as a way of inserting intact membrane phospholipids directly into neurones. A recent narrative review focused on Alzheimer’s disease (AD) described the biology as promising, but the human evidence as still unclear (Conway et al., 2024).
Lecithin tends to be a mixed phospholipid product, usually from soy or sunflower, and sits closer to food-adjacent territory than the more concentrated supplement forms.
The basic choline salts, such as choline bitartrate, are better understood as efficient ways of raising circulating choline than as precision tools aimed at particular neurological mechanisms. They are cheaper, but that simplicity comes with trade-offs. In a randomized clinical trial in healthy adults, dietary choline supplements, unlike eggs, increased fasting TMAO and potentiated platelet aggregation. That does not mean these supplements are automatically harmful in every setting, but it does justify a more cautious approach to high-dose use, particularly when the goal is vague or when cardiometabolic risk is already part of the picture (Wilcox et al., 2021).
Taken together, the evidence leads to a narrower conclusion than supplement marketing usually suggests. The best-supported human data for choline-containing supplements still sit mainly around cognition and function in selected neurological settings. The membrane, mitochondrial, oxidative stress, calcium, and inflammation stories are all scientifically relevant, but they are not yet backed by equally strong human trial evidence showing that these supplements reliably improve those mechanistic domains in ALS, PD, or AD.
So which form is best? That is still the wrong question. A much better one is what the supplement is being used for, in whom, with what trade-offs, and on what evidence.
Should someone with neurodegeneration supplement choline?
Sometimes maybe. Sometimes no. Often the more useful first move is food rather than a capsule, because the bigger nutritional issue is frequently not choline intake in the first place but inadequate calories, inadequate protein, poor tolerance of meals, or a generally fragile dietary pattern that needs broader attention before any single nutrient is fine-tuned.
There is also a meaningful difference between correcting a low intake of a nutrient, deliberately trying to influence a biological pathway, and implying that you are treating a disease. Those are not the same thing, and they should not be allowed to blur into one another.
The TMAO problem
This is the part of the conversation that complicates everything.
Choline is a precursor of TMAO, a compound made by certain gut microbes from choline and then processed by the liver. TMAO has been linked to inflammatory signalling, oxidative stress, mitochondrial dysfunction, and cardiometabolic risk, and it has also drawn attention in neurological research (Praveenraj et al., 2022).
Think of choline here as firewood and TMAO as smoke. The same fuel that warms one house cleanly can fill another room with smoke entirely, depending on how the fire is built and how well the chimney works. Choline itself is not the villain. The chimney, meaning the gut microbes, the liver, and the kidneys, determines much of the story, and two people on the same dose will rarely produce or clear the same amount.
Recent epidemiology has added caution rather than clarity. A dose-response meta-analysis by Sharifi-Zahabi and colleagues (2024) reported that higher dietary choline intake was associated with increased all-cause and cardiovascular mortality across the cohorts they pooled. That is not enough on its own to conclude that dietary choline is harmful in every setting, but it is more than enough to remind us that “more is better” is not a serious scientific position with this nutrient. The ALS-specific picture is mixed as well.
The most sensible response is neither to ignore TMAO nor to obsess over it. It is simply to recognise that high-dose choline supplementation, particularly with the cheaper salts that may feed the pathway most efficiently, against the backdrop of a struggling gut, reduced kidney function, or a poor overall diet, is not something to approach casually.
A ceiling is not a target
Reference authorities set a tolerable upper intake level of 3,500 milligrams per day for adults because high intakes can cause low blood pressure, sweating, a fishy body odour, excess salivation, and gastrointestinal symptoms (Wallace et al., 2018; Burns et al., 2025).
One of the stranger habits in supplement culture is to treat that ceiling as if it were proof that a large dose must be useful. It is not. With choline, the more sensible posture is moderation, context, and a clear reason for whatever you have decided to do.
How we think about it in clinic
If you compress all of this into a working framework, four questions cover most situations.
First, is the diet plausibly covering the basics? If intake looks low and food variety is thin, that is the place to start, before any bottle is opened.
Second, is there a biological reason to think this person may need more, such as genetics, life stage, or higher demand? That question is often more useful than average intake figures on their own.
Third, if a supplement is on the table, why? The goal is not the same for everyone. Basic nutritional adequacy, membrane support, a cognition-oriented rationale, and “I read something interesting online” are different reasons, and they point to different choices.
Fourth, what raises the risk profile? An unhappy gut, reduced kidney function, cardiometabolic concerns, or unusually high doses all push caution closer to the front of the conversation.
The smartest question is rarely “what is the best choline supplement?” It is closer to “what problem am I actually trying to solve, and is choline really the right lever for it?”
Where this leaves us
This three-part series began with biology and ended with judgement. The thread running through all three is the same: interesting biology is not a licence to oversell, and for most people the first move is not to chase a shiny capsule but to take an honest look at the diet, the context, and the actual reason for intervening at all. That message sells fewer bottles than the alternative. It is also much more likely to be true.
We are also very grateful to Dr Kirstie Lawton for sharing insights from her scoping review, Mechanisms of action of choline and molecular and clinical implications of choline deficiency in amyotrophic lateral sclerosis. Her work helped deepen and inform this series, particularly around the links between choline, cell membranes, mitochondrial function, oxidative stress, neuroinflammation, and the wider biology of ALS.
If you or someone you love is living with ALS or another neurodegenerative condition and would like personalised support around nutrition, supplements, and testing, You Nutrition Clinic is here to help. Our practitioners work across a range of neurodegenerative conditions, including support for people affected by ALS, with insight shaped by the work of Dr Kirstie Lawton and the wider team. To arrange a free initial chat, please get in touch via the website contact form or email admin@younutritionclinic.com.
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Disclaimer: This article is for informational and educational purposes only and does not constitute medical advice. Always consult with a qualified, registered medical doctor (MD) for diagnosis and treatment decisions.
References
Bonvicini, M., Travaglini, S., D’Angelo, A., Nigro, O., & Pedone, C. (2023). Is citicoline effective in preventing and slowing down dementia? A systematic review and a meta-analysis. Nutrients, 15(2), 386. https://doi.org/10.3390/nu15020386
Burns, B. C., et al. (2025). Choline: An essential nutrient with health benefits and a signaling molecule. International Journal of Molecular Sciences, 26, 7159.
Conway, T., Seidler, K., & Barrow, M. (2024). Unlocking choline’s potential in Alzheimer’s disease: A narrative review exploring the neuroprotective and neurotrophic role of phosphatidylcholine and assessing its impact on memory and learning. Clinical Nutrition ESPEN, 64, 177–195. https://doi.org/10.1016/j.clnesp.2024.09.024
da Costa, K. A., Kozyreva, O. G., Song, J., Galanko, J. A., Fischer, L. M., & Zeisel, S. H. (2006). Common genetic polymorphisms affect the human requirement for the nutrient choline. The FASEB Journal, 20(9), 1336–1344. https://doi.org/10.1096/fj.06-5730com
Fischer, L. M., da Costa, K. A., Kwock, L., Stewart, P. W., Lu, T. S., Stabler, S. P., Allen, R. H., & Zeisel, S. H. (2010). Dietary choline requirements of women: Effects of estrogen and genetic variation. The American Journal of Clinical Nutrition, 92(5), 1113–1119. https://doi.org/10.3945/ajcn.2010.29799
Ganz, A. B., Cohen, V. V., Swersky, C. C., Strochlic, D. E., O’Sullivan, R., Smith, D. E., Coene, M., Fernandez, C. A., & Freedman, J. H. (2017). Common genetic variants alter metabolism and influence dietary choline requirements. Nutrients, 9(8), 837. https://doi.org/10.3390/nu9080837
Jasielski, P., Piędel, F., Piwek, M., Rocka, A., Petit, V., & Rejdak, K. (2020). Application of citicoline in neurological disorders: A systematic review. Nutrients, 12(10), 3113. https://doi.org/10.3390/nu12103113
Obeid, R., et al. (2023). Choline: A scoping review for Nordic Nutrition Recommendations 2023. Food & Nutrition Research, 67.
Praveenraj, S. S., et al. (2022). The role of a gut microbial-derived metabolite, trimethylamine N-oxide, in neurological disorders. Molecular Neurobiology, 59(11), 6684–6700.
Que, D. L. S., Jamora, R. D. G., & de los Reyes, K. V. (2021). Citicoline as adjuvant therapy in Parkinson’s disease: A systematic review. Clinical Therapeutics, 43(1), e19–e31. https://doi.org/10.1016/j.clinthera.2020.11.002
Resseguie, M. E., da Costa, K. A., Galanko, J. A., Patel, M., Davis, I. J., & Zeisel, S. H. (2011). Aberrant estrogen regulation of phosphatidylethanolamine N-methyltransferase results in choline deficiency-associated liver dysfunction. Journal of Biological Chemistry, 286(2), 1649–1658. https://doi.org/10.1074/jbc.M110.170431
Sagaro, G. G., Battistin, L., Vecchiato, G., Carollo, C., Cagnin, A., & Manzato, E. (2023). Activity of choline alphoscerate on adult-onset cognitive dysfunctions: A systematic review and meta-analysis. Journal of Alzheimer’s Disease, 92(1), 59–70. https://doi.org/10.3233/JAD-221189
Sharifi-Zahabi, E., et al. (2024). Higher dietary choline intake is associated with increased risk of all-cause and cause-specific mortality: A systematic review and dose-response meta-analysis of cohort studies. Nutrition Research, 130, 48–66.
van der Veen, J. N., et al. (2017). The critical role of phosphatidylcholine and phosphatidylethanolamine metabolism in health and disease. Biochimica et Biophysica Acta - Biomembranes, 1859(9 Pt B), 1558–1572.
Wallace, T. C., et al. (2018). Choline: The underconsumed and underappreciated essential nutrient. Nutrition Today, 53(6), 240–253.
Wilcox, J., Brown, A., Berti, C., et al. (2021). Dietary choline supplements, but not eggs, raise fasting trimethylamine-N-oxide levels in participants with normal renal function: A randomized clinical trial. The American Journal of Clinical Nutrition, 114(4), 1163–1172. https://doi.org/10.1093/ajcn/nqab180
Zeisel, S. H. (2012). A brief history of choline. Annals of Nutrition and Metabolism, 61(3), 254–258.