Should vegans be worried about choline deficiency and their brain health?

If you’ve read the news in the past week, you might have come across one of the many articles with click-bait titles such as “Why a vegan diet might be making you dumb”, and “Vegan diets risk insufficient intake of nutrient critical for brain health”. Suddenly, it is not protein, or B12, or iron that vegans have to worry about: the new nutrient a plant-based diet could be making us deficient in is Choline. But let’s take a step back.

The background

This all began when Emma Derbyshire, a nutritionist from the United Kingdom, published an opinion piece in the medical journal BMJ Nutrition, calling for Choline, a nutrient more commonly found in meat and dairy, to be recognised as an essential nutrient in a healthy diet. [1] In this piece, she argues that vegans may be missing out on choline, and that choline deficiency may have disastrous consequences such as liver disease, offspring cognitive function and potential neurological disorder. She states that this is of particular concern given the recent rise in popularity of plant-based diets, and that caution must be exercised.  

As you can imagine, this article has already been picked up by countless news outlets – 117 to be precise [2] – and has then been shared by countless more in the pro-meat/keto/paleo camp (such as Paleo Chef Pete Evans [3], ‘Carnivore doctor’ Shawn Baker [4] and journalist Max Lugavere to name a few).

So why is this nutrient you’ve probably never heard of (and if you have, you’ve heard of it in a negative connotation) suddenly now the hot topic in nutrition?

Well, for starters, Emma Derbyshire is a member of the Meat Advisory Panel – an interest group that promotes the consumption of meat. In addition to this, Emma also consults and advises the British Egg Information Service – interestingly all of these conflicts of interest were undeclared when this opinion piece in the BMJ was first published.  Shortly after it was updated, most likely as people in the public picked up on these associations and notified the journal. After countless research has proven time and time again that meat, dairy and egg consumption is associated with poor health outcomes and is a leading cause of the destruction of our ecosystem, the meat industry is now attempting to fight back. Their new tactic? Convincing people that we are facing a choline deficiency crisis in public health – and that plant-based diets are exacerbating that crisis.

In fact, Emma directly acknowledges (quote below) the threat to animal agriculture when she cites the 2019 EAT-LANCET publication whereby 30 independent scientist’s from around the world came together and concluded that the best diet for human & planetary health was a plant focussed diet with considerably less consumption of red meat, eggs and dairy. Cleverly, we are made to believe the threat is to choline status when in fact it’s quite clearly tied to animal agriculture sales.  

The recent 2019 EAT-Lancet publication has compiled a healthy reference diet, based on an adult dietary intake of 2500 kcal/day. While this should be praised in that it is the first report to compile a healthy food plant based on promoting environmental sustainability, restricted intakes of whole milk, eggs and animal protein could impact on choline intakes and status.

In this article, I will walk you through exactly why this opinion piece article really carries zero weight and shouldn’t have you worried.

What is choline?

Before we go any further, it’s important first to establish what choline is. Choline is an essential nutrient, meaning that although our liver produces some choline, it will be necessary to consume choline via our diet for optimal intakes. [5] Choline plays an important role in the body, from regulating memory, mood, to muscle control and helps transfer signals between nerve cells. [6] This nutrient is of particular importance during pregnancy and lactation, when demand for choline is especially high and the supply of choline is critical. [7]

How much do we need – and what is the recommendation based on?

Here, the science is more contented. The fact is that we don’t really know how much we need. In fact, there is currently no RDI (Recommended Daily Intake) set for choline – only an AI (Adequate Intake). The AI for choline is 550 mg/day for adult men and 425 mg/day for adult women. [8] However, it’s worth noting that this figure was set based on one single study dating back to 1991 that looked at a tiny sample of 16 subjects, which compared intakes of 500mg/day to 50 mg/day – with no intermediary amounts examined. The study reported decreased choline stores and liver damage when men were fed the 50mg/day choline-deficient diet, and thus 500mg/day was set as the ‘safe’ level that would prevent liver damage. There is no doubt that consuming less than 50 mg/day could result in liver damage and other health issues – but it is highly unlikely that a vegan following a minimally balanced diet could reach such low intake levels. The European Food Safety Authority has also recommended adults to consume 400 mg, yet once again this figure is based on consumption data from national surveys conducted on the average person in the European Union rather than rigorous clinical trials looking at what the optimal intake level is. [9] 

Other studies have induced a choline deficiency in subjects to calculate how much choline would be required to reverse the deficiency. Results have varied, and range from 138mg/day to 825 mg/day. [10, 11]

What are the implications of sub-optimal Choline consumption – and are vegans more at risk of these implications? 

True choline deficiency can cause muscle damage, neural tube defects, liver damage, nonalcoholic fatty liver disease, neurological conditions such as dementia and Alzheimer’s, and cardiovascular disease (because of a higher concentration of homocysteine). [5, 12, 13]

When it comes to vegan intakes, no study thus far has quantified how much choline is regularly consumed by those following a plant-based diet. However, based on choline amounts in common plant-based foods (1 cup of cooked quinoa, one of the most choline-rich plant-based foods, contains a mere 42mg of choline) it is possible to assume that the average vegan is not consuming anywhere close to the AI of 550 mg/day (men) or 425 mg/day (women). So how come we don’t see vegans in hospital beds suffering from liver disease, neurological issues and cardiovascular disease? In fact, quite the opposite – rates of cardiovascular disease amongst vegans are the lowest compared to people eating beef, dairy & eggs, which are animal sources of choline [14], nonalcoholic fatty liver disease is inversely associated with plant-based foods,  [15] and incidences of neurological conditions such as dementia and Alzheimer’s are again associated with animal choline-rich protein. [16, 17]

How come children born to vegan mothers aren’t suffering from neural tube defects and vitamin deficiencies? Again, the opposite is true – it has widely been reported in the medical community that vegan pregnant women have a lower-than-average rate of cesarean delivery, less postpartum depression, and lower neonatal and maternal mortality, with no complications or negative outcomes that are higher than average. [18, 19] Further, while some preliminary findings suggested a link between choline and neural tube defects, recent research has found no relationship between choline concentrations in the blood of a pregnant woman and neural tube defects in offspring. [20] However, until we know more, although there is not enough evidence to recommend Choline supplementation during pregnancy (and in fact, Choline rarely features in Prenatal pills) it might be prudent for expectant mothers on plant-based diets to set up their diets to favour choline intake. And rest assured that, as stated by the American Dietetic Association, an appropriately planned vegan diet is considered safe, healthful and nutritionally adequate, and appropriate during all life cycle stages, including pregnancy, lactation, infancy, childhood, and adolescence. [21]

So how come the negative health outcomes related to Choline deficiency manifest rarely in vegans? There are two main reasons at play.

1. Even though vegans are probably not consuming the AI of 550 mg/day (men) or 425 mg/day (women) – so are omnivores. In fact, surveys have found that most people in the United States – where only 3% of the population is vegan [22] – consume less than the AI for choline. [23] Data from the National Health and Nutrition Examination Survey (NHANES) concluded that children and teens were consuming on average 256 mg of choline each day, adult men were consuming around 400 mg and adult women were averaging 295 mg. [24] And yet, although most people in the United States consume significantly less than the AI of choline, choline deficiency in healthy individuals is extremely rare. [25] Again, this AI has been set based on a single study – so the choline we actually need is likely to be much lower.  
2. Even though vegans are probably consuming even less choline than their omnivore counterparts, it is very unlikely they are consuming anywhere close to 50mg/day – the intake that was implicated in liver disease. In fact, although choline is more abundant in animal-based foods, it is also found in a wide range of plant foods, albeit in smaller amounts. Tofu, soy, broccoli and quinoa all contain good amounts of choline, so as long as a vegan diet is balanced and not calorie-restricted, consuming an adequate amount of choline would probably come naturally. 

In short, yes – consuming little to no choline could have negative health outcomes, but it is highly unlikely that the choline consumed in a balanced plant-based diet would be so low as to cause dangerous health effects. 

What are the implications of excess Choline consumption?

If anything, excess choline has been linked to poor health outcomes. 

For starters, choline has been linked to cardiovascular disease via the production of TMAO. [26] What is TMAO, you ask? Well, when researchers at the Cleveland Clinic screened the blood of patients who had experienced a heart attack or stroke, and compared the results with those from blood of people who had not, they identified a compound called TMAO and found that the more TMAO people had in their blood, the greater the odds they had heart disease, and the worse their heart disease was. [27, 28] Where does TMAO come from? TMAO is converted from TMA in the liver – which in turn is converted from choline and carnitine by bacteria in our gut. In other words, the more choline we ingest, the higher the TMAO levels, and the higher the risk we may have for heart disease.

Excessive choline has also been linked to a heightened risk for cancer.  A 2007 report from the Nurses’ Health Study found an association between higher choline intakes and colon cancer in women. [29] After adjusting for energy intake, folate, fibre, calcium, alcohol and red meat, they found that a choline intake of 383 mg/day had a 45% increased risk of developing colon cancer compared to the lowest intake group which consumed 293 mg/day.  

In addition, studies have linked choline intake to prostate cancer. Men consuming high levels of choline intake had a 70% increased risk of lethal prostate cancer. [30] Obviously, these associations could easily be caused by the animal protein rather than simply the choline – but it remains an interesting link nonetheless. 

So why, you might be wondering, is the Meat industry now pushing Choline when this nutrient has been majorly implicated in the development of some of our biggest-killing diseases? 

Well, I’m afraid this is nothing but the umpteenth time we’ve seen the meat/dairy/egg industry use the well-known and profitable marketing tactic of highlighting one particular nutrient while downplaying the ‘elephant in the room’. Cholesterol in eggs getting a bad press? Let’s push eggs as high-quality proteins, nutrient-dense powerhouses and a great source of choline! Saturated fat linked to heart disease in a recent big study? Better push meat as a great source of iron, protein and vitamins! Sugar in children’s breakfast cereal coming under fire? Time to market cereal as a great source of fibre and add a bunch of vitamins to boost the nutritional profile! 

In other words, this is nothing new. Conjuring up a hypothetical Choline deficiency epidemic is merely the latest attempt deployed by the meat industry to get consumers to stick to their animal-based foods and shy away from the ‘plant-based movement’. And no, this is not a conspiracy theory. The saga has been well documented by the very highly regarded Dr Micheal Gregor (a past guest on the Plant Proof podcast), who was able to get his hands on correspondence between the Egg Industry and the USDA Agriculture Marketing Service thanks to the Freedom of Information Act. For the full story, head to NutritionFacts.org, but in short, Dr Gregor was able to uncover papers in which the American Egg Board declared a priority objective to “make choline out to be an ‘urgent’ problem and eggs the solution”. The proposed way to do this?  To “partner with a physician’s group, and write an advertorial.” Then, to send out letters to doctors “warning about inadequate intake of choline having tremendous public health implications.” 

No surprise then, that the majority of the research articles on Choline have been written by individuals with connections to the egg or meat industry. 

Finding Choline on a plant-based diet.

Although excessive choline may be linked to negative health outcomes, there is no doubt that adequate consumption is necessary. And although reaching the AI recommended 400-500mg/day of choline may be a hard task on a plant-based diet (or any diet for that matter!), as detailed above, this number has been set based on just one study from 30 years ago, and it is doubtful that humans need this much to thrive. 

Therefore, although not close to the AI, a HEALTHFUL amount of choline can be easily sourced on a well-balanced plant-based diet. In fact, many foods contain choline – and although the main dietary sources of choline are primarily of animal-based products such as meat, poultry, fish, dairy products, and eggs, cruciferous vegetables, peas, certain beans, soy, nuts, seeds, and whole grains are also rich in choline. [31]  Below I’ve listed some of the most choline-rich plant foods that I’ve taken from the USDA Food Composition Database – but for a full overview of all choline in plant foods click here.

SUMMARY 

At the end of the day, the science on Choline is still very much in its infancy and constantly evolving. In this, Emma Derbyshire and I agree: nutrition research must look into the ‘long-term’ intakes of choline. Further, more research is required to identify what the RDI recommended intake for plant-based and omnivore individuals alike. 

In short,

• If you eat a balanced and varied plant-based diet, Choline is not a nutrient that deserves special attention (unlike B12, Omega 3, Vitamin D, and Iron in some cases). 

• Vegans or those eating a predominantly plant-based diet need not take a Choline supplement – however, until we know more, making sure we regularly consume plant-based foods rich in choline is a prudent move. This will easily be achieved by consuming a wide range of plant foods.
• If you are pregnant or attempting to be, Choline is of particular importance and, although approximately 90%–95% of pregnant women consume less choline than the AI [32], it is prudent to consume Choline-rich plant-based foods often and consult a trusted healthcare professional.

REFERENCES

[1] Derbyshire E. Could we be overlooking a potential choline crisis in the United Kingdom? BMJ Nutrition, Prevention & Health 2019; bmjnph–2019–000037.

[2] Report for: Could we be overlooking a potential choline crisis in the United Kingdom?, https://bmj.altmetric.com/details/65645262/news 

[3]  https://www.facebook.com/169278773165517/posts/2488097967950241?sfns=mo 

[4] Shawn Baker MD on Instagram: ‘It’s ok I can force feed my kids more supplements as we know that is the tried and true vegan approach! As each decade of vegans figures…’. Instagram, https://www.instagram.com/p/B10M-FGHGxi/ 

[5] Catharine Ross A, Caballero BH, Cousins RJ, et al. Modern nutrition in health and disease: Eleventh edition. Wolters Kluwer Health Adis (ESP), 2012.

[6] https://ods.od.nih.gov/factsheets/Choline-Consumer/ 

[7] Steven H. Zeisel K-A da C. Choline: An Essential Nutrient for Public Health. Nutr Rev 2009; 67: 615.

[8] Zeisel SH E al. Choline, an essential nutrient for humans. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/

[9] Dietary reference values: EFSA publishes advice on choline. European Food Safety Authority, https://www.efsa.europa.eu/en/press/news/160817

[10] da Costa KA E al. Elevated serum creatine phosphokinase in choline-deficient humans: mechanistic studies in C2C12 mouse myoblasts. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/15213044 

[11] Detopoulou P E al. Dietary choline and betaine intakes in relation to concentrations of inflammatory markers in healthy adults: the ATTICA study. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/18258634

[12] Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, its Panel on Folate, Vitamins OB, et al. Choline. In: Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. National Academies Press (US), 1998.

[13] Corbin K D And. Choline metabolism provides novel insights into nonalcoholic fatty liver disease and its progression. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/22134222?dopt=Abstract 

[14] Orlich MJ, Singh PN, Sabaté J, et al. Vegetarian Dietary Patterns and Mortality in Adventist Health Study 2. JAMA Intern Med 2013; 173: 1230.

[15] Chiu TH, Lin M-N, Pan W-H, et al. Vegetarian diet, food substitution, and nonalcoholic fatty liver. Tzu-Chi Medical Journal 2018; 30: 102.

[16]https://www.sciencedirect.com/science/article/pii/S0197458014003480 

[17] Giem P E al. The incidence of dementia and intake of animal products: preliminary findings from the Adventist Health Study. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/8327020 

[18] Carter JP E al. Preeclampsia and reproductive performance in a community of vegans. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/3589760

[19] Pistollato F, Cano SS, Elio I, et al. Plant-Based and Plant-Rich Diet Patterns during Gestation: Beneficial Effects and Possible Shortcomings. Adv Nutr 2015; 6: 581.

[20] Mills JL E al. Maternal choline concentrations during pregnancy and choline-related genetic variants as risk factors for neural tube defects. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/25240073?dopt=Abstract 

[21] Website, https://www.ncbi.nlm.nih.gov/pubmed/19562864

[22] Reinhart by RJ. Snapshot: Few Americans Vegetarian or Vegan. Gallup.com, https://news.gallup.com/poll/238328/snapshot-few-americans-vegetarian-vegan.aspx 

[23] Office of Dietary Supplements – Choline, https://ods.od.nih.gov/factsheets/Choline-HealthProfessional/.

[24] WWEIA Data Tables : USDA ARS, https://www.ars.usda.gov/northeast-area/beltsville-md-bhnrc/beltsville-human-nutrition-research-center/food-surveys-research-group/docs/wweia-data-tables/ 

[25] Office of Dietary Supplements – Choline, https://ods.od.nih.gov/factsheets/Choline-HealthProfessional/ 

[26] Zhu W, Zeneng W, Wilson Tang WH, et al. Gut Microbe-Generated TMAO from Dietary Choline Is Prothrombotic in Subjects. Circulation 2017; 135: 1671.

[27] Michael Greger M. Egg Industry Response to Choline & TMAO | NutritionFacts.org, https://nutritionfacts.org/video/egg-industry-response-to-choline-and-tmao/

[28] Li XS, Wang Z, Cajka T, et al. Untargeted metabolomics identifies trimethyllysine, a TMAO-producing nutrient precursor, as a predictor of incident cardiovascular disease risk. JCI Insight; 3. Epub ahead of print 22 March 2018. DOI: 10.1172/jci.insight.99096.

[29] Cho E E al. Dietary choline and betaine and the risk of distal colorectal adenoma in women. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/17686825

[30] Richman EL, Kenfield SA, Stampfer MJ, et al. Choline intake and risk of lethal prostate cancer: incidence and survival. Am J Clin Nutr 2012; 96: 855.

[31] Office of Dietary Supplements – Choline, https://ods.od.nih.gov/factsheets/Choline-HealthProfessional/

[32] Brunst KJ E al. Racial/ethnic and sociodemographic factors associated with micronutrient intakes and inadequacies among pregnant women in an urban US population. – PubMed – NCBI, https://www.ncbi.nlm.nih.gov/pubmed/24476840?dopt=Abstract