Nutrients of Concern
Nutrients of Actual Concern
B12
Everybody, vegan and non-vegan, should supplement for vitamin B-12. As a water soluble vitamin, it's extremely safe, does not promote risk of overdose, and ensures good levels of the vitamin which is necessary for many vital functions from cell division (particularly blood cells) to nerve function.
A typical recommended dosage is from 25 - 100 mcg a day (which is what is found in many supplements). See recommendations for details.
Most people, including most meat-eaters, show sub-optimal levels and some even borderline deficiency in B-12. This is because B-12 does not "come from" meat, it is produced by bacteria, and not animals. Small amounts exist in animals because of what the animals ate, from enteric fermentation, or what supplements the animals were given. Wild herbivores including Chimpanzees (our closest relative and mostly herbivorous with under 10% of calories from animal products), gorillas, and other non-ruminant animals, primarily obtain B-12 from the practice of coprophagy and other environmental contamination (not safe, not recommended).
Most animal products are not very good sources of B-12. Beef liver is an exception, because that's where a large amount of B-12 is stored, but exceptions like these are not very popular foods for most people.
However, vegans are at higher risk of severe deficiency. While everybody should supplement B-12, vegans not only should but must supplement B-12. All vegans, every vegan. This is consensus, and endorsed by every major vegan advocacy group and professional:
The Vegan Society (UK), People for the Ethical Treatment of Animals, Michael Greger MD, EVA – Ethisch Vegetarisch Alternatief Belgium, Farm Animal Reform Movement (FARM), Portuguese Vegetarian Association (Associação Portuguesa Vegetariana), Vegan Action (US), Vegan Outreach (US), and over a dozen other professionals.[1]
While most omnivores get barely enough B-12 to function (since animal products usually contain at least a very tiny amount of B-12, aside from honey which contains none), vegans who do not supplement or regularly eat fortified foods are at risk of getting virtually no B-12 at all because there is no safe and reliable vegan source aside from supplementation (not seaweed, not algae, not organic vegetables; some have traces, but also have B-12 analogues that interfere with absorption, and none enough to reliably correct deficiency), and this can lead to serious complications like nerve damage if not recognized and treated immediately (High folate consumption can mask the earlier signs of deficiency like megaloblastic anemia).
Please do not compromise the health benefits of a vegan diet by doing something foolish like neglecting a simple, cheap, and safe and reliable supplement.
B-12 stores
It's true that some people have large B-12 stores and can go vegan and then wait many years without supplementing, subsisting on their body's stored up B-12 from when they were omnivores.
But consider this: If we know that even most omnivores are borderline deficient, how is it that new vegans would have any reserves to draw from?
The answer: They probably don't.
If you were a regular consumer of beef liver as an omnivore and just went vegan, you may in fact have plenty of B-12 stored up to last you years. But if you ate a typical omnivore diet, you were probably already borderline deficient, or possibly already deficient in B-12. In the latter case, you will have no stores to fall back on, and you should supplement immediately to be safe. Even if you ate a significant amount of liver, B-12 absorption varies by individual and that is no guarantee. There is no test for B-12 storage, so the only guarantee against deficiency is to have a regular and reliable source of B-12.
B-12 Testing
To make matters worse, because of the often high levels of B-12 analogues (fake B-12) in vegan diets from foods like seaweed, a typical B-12 blood test is not reliable. The only reliable test is a test for Methylmalonic Acid levels, which rise as a result of B-12 deficiency. This test is not common and is something you would probably have to pay for out-of-pocket. There's no reason to waste money on a blood test when:
- Supplements are cheaper than the blood test, at pennies a day
- If you have no B-12 source, we already know your levels will be low or will soon become low as your minimal stores are depleted (there is no test for B-12 storage, and because you won't be testing every week a normal test result could give you a false sense of security).
- Excess B-12 is harmless in most people (it's actually one of the safest vitamins there are) Megadoses (well in excess of that required) may create mild acne-like symptoms, but reducing the dose to a normal level will reverse this. The only known exception is in smokers, covered below here.
If you are supplementing and you want a test for peace of mind, then you can order a MMA test to confirm your supplements are working.
B-12 & cancer
High intake of B-12 supplementation (over 55 mcg a day) in addition to large dietary intake seems to significantly increase risk of lung cancer in smokers.[2]
There's no consistent evidence to suggest this effect applies to non-smokers (due to the much smaller risk non-smokers are at, and small sample size of non-smokers who develop lung cancer), and particularly in never-smokers, but it may also apply to people exposed to very large amounts of second hand smoke and people who have smoked in the recent past (all vulnerable to the same cancers smokers are).
There's also no evidence that supplementation at levels vegans typically take alone without high dietary intake can result in this outcome for vegan smokers, although it is plausible (In one analysis there was no effect in female smokers, who had lower dietary intake of B-12, and there was no association with multivitamin use containing B-12[3]).
There are a couple non-exclusive possibilities for the effect relative to absorption:
1. It may be the overall higher level of B-12 in the blood in general (as a result of good absorption and adequate status)
2. It may be due to shorter term spikes in blood concentration of B-12 after a particularly large absorbed dose (before it has time to be stored away where the cancer has no access to it)
In the former case, without high levels of dietary B-12 the effect would likely only manifest at much higher supplement levels; possibly higher than 100 mcg a day (because proportionally less is absorbed through single supplements than from dietary sources throughout the day), and any dosage with comparable absorption, such as over 1000 mcg twice a week. The lack of correlation in women for some studies may support this, indicating a threshold of B-12 levels that must be passed for the effect to appear.
In the latter case, large supplement doses may be a concern in themselves, particularly twice a week doses which must be larger to provide enough absorbed B-12 for the non-supplementing days. Smaller, more spread-out doses would help facilitate absorption and storage for adequate status without peaks in B-12 concentration speculatively accessible to the cancer cells.
To be clear, B-12 is not believed to *cause* cancer; it is not a carcinogen or a mutagen, and there is no mechanism by which it would be expected to directly increase risk on its own.
Rather, the mechanism of action seems to be that high B-12 status may be protective or nutritive of cancer cells that already exist (cause by the smoking).
Protective effects could come from reducing the effects of the smoke on the cancer (and it would make the most sense if this applies to overall/average blood B-12 levels, with minor spikes in blood B-12 levels not being particularly relevant).
Cigarette smoke is a double edged sword, both causing cancer and killing cancer cells (on balance, it does the former quite a bit more than the latter).
B-12 sequesters and is used in detoxification of one of the main poisons in cigarette smoke, cyanide, which kills cancer. Of course cyanide kills normal cells too and alt-med cyanide therapy can be deadly[4], but some therapies are being developed to target cancer cells with cyanide producing enzymes[5] so this may be a viable treatment in the future.
By this mechanism large amounts of B-12 may be protective of cancer cells from the deadly effects of cigarette smoke while not offering any protection to normal cells from the carcinogenic effects of the smoke, thus increasing risk of cancer development by further dulling the protective edge of the double edged sword of cigarette smoke in cancer development.
It may also be possible that, by deactivating free B-12 in the lungs, cigarette smoke deprives cancer cells of an essential vitamin for growth and cell function. B-12 is needed for methionine production from homocysteine using certain enzymes[6] In the unique high-cyanide environment of the smoker's lung, B-12 may be a limiting factor to growth. In this case, spikes in B-12 may temporarily overcome the effects of the smoke and provide cancer adequate B-12 to grow during the period after high doses.
A combination of these two mechanisms, or others, may be responsible. Either way, it's the combination of the smoke causing cancer and either protective or nutritive effects of the B-12 for the cancer in the unique environment of a smoker's lung, not the B-12 alone, and it only occurs with larger doses and is only correlated with increased cancer risk for primarily smoking-caused cancer types, not in adenocarcinoma (which is less related to smoking)[7].
Recommendations
B-12 absorption is is better in small amounts, spread out over time.
Jack Norris of Veganhealth.com has a convenient table for reference[8] <img src="https://philosophicalvegan.com/images/B12recs.jpg">
If you are supplementing daily, 25-100 mcg is adequate (and can be found in some vegan multivitamins). If you are supplementing only twice a week, you will need 1,000 mcg each time (also a common supplement amount for dedicated B-12 supplements) which averages to almost 300 mcg a day. Larger doses like this slightly increase the risk of minor acne-like side effects, which can be eliminated by taking smaller supplements more frequently.
The science so far is pretty conclusive: the recommended form is cyanocobalamin because it is very stable and reliable. Other forms may be less stable. The trace of cyanide in 100 mcg of B-12 is not harmful, and it is comparable to the natural levels of cyanide in other healthy foods like almonds, but is actually safer than those forms because B-12 binds and neutralizes cyanide preventing acute effect even from huge doses. Even without the B-12, you would need thousands of times the amount to pose a risk (the dose makes the poison).
B-12 shots are not recommended.
A liquid supplement poses no risk and is suitable for anybody, and pills pose virtually no risk (they can be choking hazards for young children), but a shot can (in a freak accident) hit a nerve and cause serious damage.
Vegans using shots for B-12 also mislead people into thinking they need to get shots to go vegan, and this has been used as a reason not to go vegan (fear of needles is very common).
Please do not get B-12 shots unless ordered by a doctor.
For Smokers
For smokers, the issue is more complicated by the fact that high levels of B-12 supplementation have been correlated with cancer formation as discussed above.
The best recommendation to smokers is this: Stop smoking. It's a recommendation echoed by every major health organization in the world.
But if you will not or can not stop smoking, it may be wise to limit supplementation to 25 mcg a day which would both avoid the blood level spikes and hopefully keep your overall B-12 status high enough to avoid nerve damage but low enough to avoid the increased cancer risk and maintain the likely poisonous effects of cigarette smoke's cyanide on developing cancer cells and/or deny the cancer B-12 for vital functions (whatever the mechanisms may be).
Smokers choosing to limit B-12 supplementation, because of the possible effect of smoking on causing more loss of B-12 and increasing the need for it, might be served by occasional MMA tests to ensure adequate B-12 status, particularly if experiencing symptoms of deficiency.
Vitamin D
This isn't just a vegan issue, everybody needs Vitamin D. While it is true that your body can make it from sunlight pretty easily IF you get enough direct and intense sunlight, sun based production has a few serious drawbacks in terms of safety and reliability:
- Skin Cancer Risk
"Skin cancer is the most common cancer in the United States.1-2"
While it is possible that some dietary factors (like eating more vegetables) may slightly reduce skin cancer risk, being vegan alone, or any dietary measure (including a tomato only diet to maximize lycopene) is not a reliable way to protect you from skin cancer.
"Current estimates are that one in five Americans will develop skin cancer in their lifetime.3-4"
-American Academy of Dermatology[9]
"Because exposure to UV light is the most preventable risk factor for all skin cancers,6 the American Academy of Dermatology encourages everyone to protect their skin from the sun’s harmful UV rays by seeking shade, wearing protective clothing and using a sunscreen with a Sun Protection Factor of 30 or higher."
- Darker Skin Produces Less, as does wearing sunscreen (as recommended to prevent skin cancer)
To be clear, if you're out in the sun for more than a few minutes, particularly in the summer, and you have light skin you should be using sunscreen (a physical zinc-based sunscreen is probably optimal, since chemical sunscreens have to be reapplied every couple hours). BUT sunscreen does in theory limit vitamin D production by blocking UVB rays (in practice, people out in the sun for a long time will probably still produce enough). There's no way to completely cheat the system here; if you're producing adequate vitamin D form the sun, you're also increasing your risk of skin cancer. - Low UV regions and times of year can lead to inadequate production.
High Latitudes, Winter, and cloudy seasons are all issues. Air pollution is even an issue (it scatters and absorbs UVB). When attempting to get adequate vitamin D production from the sun, it's important to know the UV index, and this can be hard to keep track of. Some days you may literally need to spend hours outside, or for some people, you may need more hours of sunlight than the day is long. Your needs and the ability of the sun in your area to meet them are not easy to predict.
This is not a unique issue for vegans, most animal products "naturally" contain very little vitamin D. However, some common non-vegan products on the market like cow milk and some breakfast cereals are often fortified with added vitamin D3 (usually animal based), and vegans don't always drink fortified plant milks or eat fortified cereal. Because of this, vegans can be at a higher risk for low vitamin D levels if they do not supplement or get adequate sun exposure for their skin types, which can result in a feeling of being generally unwell/having low energy even in levels below clinical deficiency. [more info here]
There is one vegan food that can contain vitamin D without being fortified: UV exposed mushrooms. However, this is not likely to be a practical or reliable source for most people. Not only are they inordinately expensive as a vitamin D source, but it's not clear how much vitamin D is going to be present in the mushrooms due to type, duration of exposure, and how long it has been since the mushrooms were exposed and the storage conditions. It's also not clear how well the vitamin D in mushrooms would be absorbed since it may depends on other variables like food preparation and even how well you chew your food.
Oysters are also a source of vitamin D for ostrovegans, but come with many of the same issues as mushrooms in terms of variability.
The cheapest and most reliable source is supplementation.
Most multivitamins are a good option. Vegan multivitamins usually contain D2, which is an adequate source.
Vitamin D2 is plant based Vitamin D3 is usually derived from lanolin, or sheep wool grease There is vegan D3 on the market derived from lichen, but it's not used in any fortified foods yet
Animal derived vitamin D3 in food or supplements is probably an issue of least concern in terms of animal welfare. See trace animal products and byproducts. If you can only find non-vegan vitamin D3, remember this is a tiny trace of animal derived ingredient; it would be better to take this and otherwise stay vegan, and be a healthy vegan, rather than not take it and feel bad risking recidivism or ill health (you can't do much to help the animals if you aren't healthy).
If you already get ample sun exposure due to your current lifestyle check your local UV index against your skin type: you probably don't need to supplement vitamin D, although it would still be a good idea to start reducing exposure, wearing more sunscreen, and supplementing instead if that is an option for you. If you do not get much sun exposure, it would be ill advised to go out of your way to get more sun exposure for vitamin D production when supplements are easier and safer.
Omega 3, EPA & DHA
Omega 3 ALA can be obtained from whole plant sources (like walnuts, hempseeds, chiaseeds, flax seeds) and some oils (like canola) The body can convert Omega 3 ALA into needed EPA/DHA so these aren't necessary as supplements for most people. There are a couple caveats:
1. You have to avoid getting too much Omega 6 in your diet, because this can interfere with conversion. A ratio of 1:4 Omega 3 to 6 is often recommended, although the ideal ratio is not known trying to keep to this 1:4 (or more omega 3, as much as 1:1) is a good idea if you are not supplementing DHA/EPA 1. Pregnant women and young children should probably supplement to be safe. It may be important for brain health in infants (DHA/EPA are included in infant formulas) 2. Conversion in older people (after middle age) can be poor, so it's a good idea to supplement later in life
If you supplement, DHA should be adequate since it is readily converted into EPA (much more easily than Omega 3 ALA)
Calcium
Calcium can be obtained from whole plant sources like dark leafy greens, and particularly collards. However, the U.S. RDI for calcium is abnormally high and can be hard for vegans to meet unless they really love eating a lot of leafy vegetables, so for many vegans supplementation can be convenient. Fortified plant milks, and even calcium based antacids are good convenient sources (the latter is available world-wide and very cheap).
That said, RDI in other countries tends to be lower. In the UK it is 700 mg, which is much easier for vegans to meet with a sensible amount of vegetables and legumes. There's reason to believe this is probably adequate (although growing teens may need more), bone health is much more dependent on good sources of Vitamin D and exercise than upon calcium consumption beyond a certain point.
Calcium, however, is also correlated with reduced risk for some cancers... so getting the minimum for bone health may not be optimal.
Zinc
Zinc is mainly an issue for vegans who eat low fat or low protein diets. In protein and fat rich foods like legumes and nuts, zinc is a pretty prevalent mineral and at least for women hard not to get enough of if eating appropriate amounts of these.
For men it may be more difficult since Zinc is exhausted in seminal fluid, so a modest supplement, or a focus on eating more pumpkin seeds and other rich sources, may be a good idea.
If you're eating a varied diet rich in plant proteins and fats from mostly whole food sources, check some sample days in a nutrition tracking app and see if you're meeting the RDA of 11 mg for men and 8 for women (you probably are, or at least close). If you are, supplementation is probably unnecessary. While phytates can bind zinc, it's very likely that most people will adapt and upregulate absorption to compensate.
For those with complexion problems, Zinc is also one of the only supplements with good evidence of efficacy (in modest doses) for improving skin.[10] Problems may indicate poor Zinc status and suggest using a modest supplement or paying more attention to zinc intake.[11] Precaution should be used, because Zinc supplements are not without risk. Remember that the tolerable upper intake for Zinc is 40 mg/day. [12]
Iron
Iron is easily obtained from plant sources, particularly if you're eating enough protein from whole plant foods. Consuming vitamin C with an iron rich meal, however, can help with absorption.
For men this is rarely an issue. It is occasionally an issue for pre-menopausal women due to monthly iron loss through bleeding. If you have heavy periods, paying close attention to your iron consumption and focusing on lentils and other good iron sources with Vitamin C will likely be adequate. If not, a modest iron supplement may be helpful; however, you should talk to your doctor to ascertain that you are in fact low in iron before taking anything more significant than a multivitamin. Iron supplements can be dangerous.
If you do need to supplement iron can upset the stomach, so following your doctor's dosing advice but spacing out the supplement throughout the day may help.
Vitamin A
Your body converts beta-carotene into vitamin A, but the efficiency is low so large doses are needed. You can overdose on preformed vitamin A, but not on dietary carotene sources because your body will not poison itself by over-converting (worse case, your skin can become temporarily orange if you eat huge amounts).
Vitamin A in the form of beta-carotene is easily obtained from some specific carotene rich plant foods like carrots, sweet potatoes, and pumpkin, but is very difficult to find in concentrated sources in other foods. Leafy vegetables are also a source, but only if consumed in very large amounts (which most people won't do).
Most other vegan staples like grains and legumes are poor sources, so it's important to consume rich sources daily for optimal health. Some plant milks are also fortified with Vitamin A, and most multivitamins contain it. This is not necessary, but can be convenient if you don't want to worry about eating carrots/sweet potato/pumpkin every day.
Nutrients of Marginal concern
Protein
It's very easy to get enough protein overall on a vegan diet to avoid clinical deficiency, and it is true that it's difficult to become clinically deficient on a mostly whole foods diet unless not eating enough calories or getting the vast majority of calories from starches and sweet fruit (or on a less whole foods diet by consuming processed foods high in starch, sugar and oil).
However, for vegans not eating legumes, particularly if on relatively high-carb diets, it can be easy to get inadequate amounts of lysine. It may not put you in the hospital, but it can make you look and feel terrible.
Lysine is an essential amino acid, and not getting quite enough of it can have serious consequences to hair, skin, bone-health, muscle function, and immune system.
Luckily, this is relatively easy to fix with some dietary changes.
1. Increasing overall protein to around 80 grams will usually fill the gap even with relatively poor sources of lysine like wheat or corn. Keep and eye on your total, and if you hit 80 you'll probably be safe. This is the easiest way to meet lysine needs and have adequate complete protein without worrying about how much different sources have.
2. If you wish to eat a lower protein diet (or need to do so for medical reasons like kidney disease), you can supplement your diet with a few rich sources in the form of certain beans and legumes. While legumes vary in lysine content per serving and per calorie, at least two (preferably more) servings a day of soy products, peas, or an assortment of other legumes (be sure to eat a variety) can probably give you enough of a lysine boost to meet your needs even if the rest of your diet is otherwise poor (such as largely from grains and fruit).
Two servings of green peas, for example, contain 25% of your daily lysine needs, and two servings of chickpeas contains over 50%.
Some legumes, like peanuts, are rich sources per gram, but not as rich sources as other beans per calorie (roughly 1/3rd compared other beans on a calorie basis), so if you are trying to increase your lysine consumption without increasing calories that may be something to consider.
If you don't like other beans and rely mostly on peanut butter, you may need to eat an extra serving or two to get enough if you're reducing other food intake to make room for the extra calories. You can track your lysine consumption for most foods through nutrition tracking websites and apps if you have strict calorie or low protein goals.
Here's a table of lysine rich foods for convenience (but please don't rely on this alone, nutrition data can occasionally be in error):
| Lysine per | 100 calories | 100 grams |
|---|---|---|
| Boiled Lentils | 27% | 31% |
| Black Beans | 23% | 30% |
| Pinto Beans | 22% | 31% |
| Broccoli | 22% | 8% |
| Green Peas | 19% | 15% |
| Chickpeas | 18% | 29% |
| Watermelon | 10% | 3% |
| Peanut Butter | 7% | 42% |
Leafy green vegetables like broccoli are good sources of lysine per calorie (and good sources of almost everything by calorie), but they are poorer sources by weight and volume making it difficult to use them as a source (most people find it difficult to eat large volumes of vegetables). Watermelon is a rare rich source of lysine per calorie outside of legumes and vegetables, but due to high water content watermelon is very low in lysine by weight, so if using it as a source a large amount needs to be eaten daily which probably is not practical. It's included in the table as an example of a impractical but theoretically good source.
It can be complicated to restrict calories and total protein, so for most people the best advice is just to eat more protein overall and not worry about amino acids. Again, as long as you're eating ~80g of total protein you shouldn't need to worry about it. If you're suffering from kidney disease and obesity, and for medical reasons (in consultation with your doctor) you have determined that you need to restrict protein and calories, your best option would be to visit a dietitian to help you plan your diet more carefully to ensure you meet your amino acid needs on a low protein low calorie diet.
The second issue with protein has nothing to do with biological needs: Satiation.
People often complain of vegan food not being very satiating, and a major reason for this can be the lower protein concentration. Total protein is satiating regardless of the amino acid profile.
While people on standard American diets have been accused of being "proteinaholics", it does nothing for vegan outreach to promote vegan food that leaves people feeling unsatisfied. There's also no health reason to do it.
Unless you're suffering from kidney disease or have gone into ketosis due to inadequate calories from non-protein sources, it's a Myth that protein in itself is harmful.
Harm derives only from the type of protein. Longevity studies in animals have linked specific amino acids, like methionine, with shortened lifespan, and there's mechanistic evidence to believe these proteins in excess are harmful to humans as well. As it so happens, most plant proteins are significantly lower in methionine than animal proteins; only sesame seeds and brazil nuts stand out as rich sources among plant foods. If you're after optimal nutrition, it's probably a good idea to go easy on the sesame and brazil nuts, but otherwise there's no good reason to fear plant proteins as a satiating component of the diet.
Aiming for 100 grams of protein a day can not only help ensure complete nutrition given varying amounts of amino acids in plant proteins (meaning you never have to think about amino acids), but since that's comparable to levels consumed in a typical western diet it can help prevent an unsatiated feeling, and ensure that vegan food options are satisfying alternatives for the mainstream.
Legumes are among the best, easiest, and healthiest sources of protein for vegans or anybody who can eat them, they count as a protein source and due to fiber and phytonutrients are like vegetables too. Legumes are healthiest eaten cooked or fermented (as in tempeh or natto), but while some can be eaten raw (like green peas), others are toxic unless fully cooked (cooking breaks down the toxins). Many plant-based meats (Mock meats) are made from legume products and protein and some made from grain protein, some are closer to whole foods like tofu and some are more processed. Those made from legumes and legume protein are good sources of lysine. While plant-based meats tend to lack as much fiber and the phytonutrients as beans (meaning they unfortunately don't act like vegetables), they're also good sources of protein and are usually a healthy and satiating addition to the diet.
Bodybuilding
More than about 0.75 grams per lb of body weight seems to be unnecessary for most body builders, and this is easy to get on a vegan diet without any protein supplements (if desired, although protein powders can be convenient for recovery smoothies). The only thing one need be mindful of is choosing more legumes and avoiding too many starchy or fatty foods which are lower in protein; very high carb diets (like starch solution, 80/10/10) are not suitable for bodybuilding, although may be suitable for very high cardio athleticism where extra calories are being expended.
Even for vegan diets high in protein rich legumes, there is concern that the lower concentration of amino acids such as methionine and leucine may in theory make the protein slightly less effective in a competitive setting. Additionally, consuming fiber with meals can reduce absorption of protein.
There's limited research into these issues, but they don't seem to be a limiting factor for high profile vegan bodybuilders and athletes like Patrik Baboumian and Clarence Kennedy.
If you are concerned that you aren't achieving optimal performance, you can always experiment with amino acid supplementation. Supplements are typically produced by bacteria, and isolated amino acids are relatively cheap and easy to find online.
Keep in mind that supplementing with those substances which are thought to be one of the the reasons diets high in animal products are inferior in health outcomes to plant based diets may reduce or eliminate the likely health benefits of veganism with respect to longevity and chronic disease.
Choline
Adequate choline, even by the standards of DRI, is relatively easy to obtain on a vegan diet which is rich in cruciferous vegetables (like broccoli) and soy products, which are both rich sources. Cereal grains are usually not good sources, with the exception of quinoa (which is, although technically a pseudocereal).
Vegans who do not eat these products may have significant trouble reaching the DRI.
However, this is only important for some people, and it is not necessarily a good idea for everybody to reach the DRI for choline.
We do not like to recommend intentionally falling short of the DRI, but there are occasional circumstances where the DRI is not based on good evidence, and may even go against good advice for optimal health.
Choline recommendations are an issue complicated by several factors:
1. We don't really know how much choline we need within a reasonable range. We know 425 mg and 550 mg for women and men respectively is adequate for pretty much everyone, and we know 50 mg is inadequate and leads to liver damage, but this leaves a huge span of unknown.
2. Choline is not harmless. Not only does choline feed certain kinds of growing cancer cells (not directly cause cancer, but feed it if it's already there), but choline is metabolized by gut microbes into trimethylene N-oxide (TMAO) which promotes blood clotting and increases the risk of cardiovascular events from strokes to heart attacks.
3. There is considerable variability in human genetics, with some people needing more or less. Children and pregnant women may also need additional choline to reduce risk of cognitive effects.
In his summary on Choline, Jack Norris notes that ideal amounts for disease prevention seem to be around 300 mg a day, and that this probably isn't an issue for most vegans:
"The data on choline and chronic disease (cardiovascular disease, dementia, and cancer) is somewhat mixed. Ideal amounts appear to be about 300 mg per day. Most vegans probably get about that much from the foods they eat."
As noted above there are some exceptions. Pregnant and breastfeeding women should make sure to get the DRI, for which a modest supplement would probably be helpful (in practice it can be very difficult for pregnant women to get enough Choline, particularly as a major source -- vegetables -- is often off the menu).
Also people who suspect poor liver function should talk to their doctors and consider supplementation.
Young children and teens are at low risk of having developed cancer to feed and likely have very low risk of cardiovascular issues, and so should also get the DRI to ensure proper development since at that age higher levels of choline present little risk.
Otherwise, the generally lower levels of choline in a vegan diet vs. omnivorous diets are probably one protective aspect in adults and there seems to be no compelling reason for vegans to go out of their ways to meet the DRI when the effects of doing so are more likely harmful than helpful in most non-pregnant adults.
