# Do vegans/vegetarians have to do vitamin-counting to make sure they don't overdose? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [November 13, 2023, 9:13pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084 "2023-11-13T21:13:57Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Velocity](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/velocity/32/18006_2.png) [@Velocity](https://boards.straightdope.com/u/Velocity)\ **Post date:** [November 13, 2023, 9:13pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/1 "2023-11-13T21:13:57Z")
I’ve been trying to go vegetable-heavy on my diet (all those decades of refined flour, carbs, meat, sugar, salt, took a toll on my body) but I’m surprised at how packed a lot of these vegetables are. Even just one cup of collard greens, for instance, contains 8x the recommended daily value for vitamin-K. What sort of vegetables can I chow down on in large scale without having to worry about exceeding the limits? I don’t want to be just eating lots of corn, peas, sweet potatoes, etc., but anything that’s a dark green or dark red/purple vegetable seems to push one over the threshold really quickly for the hard-to-excrete stuff like Vitamin A, B, K, D, iron and folate. Vitamin C, of course, is no problem; the body just puts the excess in urine. ---
**Author:** ![griffin1977](https://avatars.discourse-cdn.com/v4/letter/g/977dab/32.png) [@griffin1977](https://boards.straightdope.com/u/griffin1977)\ **Post date:** [November 13, 2023, 9:35pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/2 "2023-11-13T21:35:12Z")
I don’t think the maths work out. For starters you can’t g[et a dangerous does of Vitamin K orally.](https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency,-dependency,-and-toxicity/vitamin-k-toxicity) e.g. Vitamin A can be dangerous. But to get to a dangerous dose ([3000mcg per day over a long period](https://www.mayoclinic.org/drugs-supplements-vitamin-a/art-20365945)) you’d need to _average_ well over over a kilogram of collard greens a day (and I suspect, though I’m not a doctor or nutritionist getting that dose through actual food rather than concentrated in a supplement would be less harmful because of all the fiber and such that your body would need to break down) Eating polar bear liver on the other hand probably a bad idea 🙂 > **[Will you die if you eat a polar bear’s liver?](https://www.sciencefocus.com/the-human-body/will-you-die-if-you-eat-a-polar-bears-liver)** > > If you’re hungry in the Arctic, you might want to think twice before tucking into that polar bear pâté. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [November 13, 2023, 9:40pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/3 "2023-11-13T21:40:12Z")
I am not a nutritionist, vegetarian, or anything like that, but I think if you spread things out over a wide variety of veggies, fruits, tubers, and what-have-you, there should be no concern with OD-ing on any one specific nutrient - I suspect you would have to eat something in quantities vastly more than your digestive system could handle, day-after-day, to get into trouble with some vitamin, so you would have other things to worry about if you tried. Go ahead and load-up on the veggies! ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 13, 2023, 10:06pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/4 "2023-11-13T22:06:34Z")
> [@Velocity](#): > > I don’t want to be just eating lots of corn, peas, sweet potatoes, etc., but anything that’s a dark green or dark red/purple vegetable seems to push one over the threshold really quickly for the hard-to-excrete stuff like Vitamin A, B, K, D, iron and folate. It is hard to get even enough Vit D from plants. > **[Here’s How to Get More Vitamin D: From Soaking Up the Sun to Eating...](https://vegnews.com/vitamin-d-vegan-diet)** > > While we can get it from the sun, it’s not always easy to get sufficient amounts of vitamin D. Here’s how to get enough on a vegan diet.   Vitamin A from plants is in the form of beta-carotene. If you get too much your skin turns kinda orange, but nothing harmful in any normal consumption. It’s Vit A from animal sources or supplements that can be dangerous. Iron should not be a problem- > **[What You Didn't Know About Plant-based Iron - Lauren McNeill, RD, MPH](https://www.tastingtothrive.com/plant-based-iron/)** > > Tell someone you’re following a plant-based diet, and they’re bound to ask you if you’re low in iron. But why is iron important to our health, and how much do we really need? Let's find out. Basically, if you dont over supplement, and stay away from a couple rare livers, you should not be able to overdose. > [@snowthx](#): > > I am not a nutritionist, vegetarian, or anything like that, but I think if you spread things out over a wide variety of veggies, fruits, tubers, and what-have-you, there should be no concern with OD-ing on any one specific nutrient - I suspect you would have to eat something in quantities vastly more than your digestive system could handle, day-after-day, to get into trouble with some vitamin, so you would have other things to worry about if you tried. Go ahead and load-up on the veggies! More or less correct. Vegans do need a B12 supplement, no plants have it. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 13, 2023, 11:39pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/5 "2023-11-13T23:39:43Z")
Remember, the RDA values for vitamins are the recommended minimum. Most vitamins either don’t have a known safe maximum, or the known safe maximum is orders of magnitude higher than the minimum. > [@DrDeth](#): > > Vitamin A from plants is in the form of beta-carotene. If you get too much your skin turns kinda orange, but nothing harmful in any normal consumption. This happened to a friend of mine, as a child. He just really, really liked carrots. His parents and doctor were worried, until they realized the cause. ---
**Author:** ![Chingon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chingon/32/17645_2.png) [@Chingon](https://boards.straightdope.com/u/Chingon)\ **Post date:** [November 13, 2023, 11:47pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/6 "2023-11-13T23:47:34Z")
If prepared collared greens contained a lethal dose of vitamin k in a typical serving size, I have to think we humans would have uncovered that secret by now. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [November 14, 2023, 2:11am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/7 "2023-11-14T02:11:10Z")
What I find interesting is that humans cannot survive a vegan diet over the long term. There is no plant source of vitamin B12. I suspect an insect supplement will suffice though. We need only a tiny dose. **But we do need it.** ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 14, 2023, 2:19am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/8 "2023-11-14T02:19:12Z")
Yeah, most “vegetarians” throughout history have gotten enough from insect contamination of their usual food source. Nowadays, you might not get that, but vitamin tablets are easy to come by. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 14, 2023, 2:41am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/9 "2023-11-14T02:41:00Z")
> [@Hari\_Seldon](#): > > What I find interesting is that humans cannot survive a vegan diet over the long term. There is no plant source of vitamin B12. I suspect an insect supplement will suffice though. We need only a tiny dose. **But we do need it.** Plenty in dairy , and some in fermented soy. (The soy doesnt have the B12, the bacteria make it ) > [@Chronos](#): > > Yeah, most “vegetarians” throughout history have gotten enough from insect contamination of their usual food source. Well, Vegetarian eat cheese, etc, so thats fine, but Vegans have only fermented soy. And sure, insects. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [November 14, 2023, 2:51am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/10 "2023-11-14T02:51:48Z")
I once had a customer who was picking up a new prescription of Coumadin (warfarin), a vitamin K antagonist that is used as a blood thinner, and when she looked at the dietary warnings, said, “Wait, I can’t have collard greens? If I can’t have those, I won’t take this!” I told her not to do that, and to talk to her dietitian. Most people on Coumadin, after their dosage is regulated, can have greens in moderation. As for turning orange, when I was in junior high in the late 1970s, someone came out with “Tanning Pills”, which gave one’s skin an orange tinge if taken as prescribed. That was probably from beta carotene, and one of my classmates bought a bottle and smuggled it into the house, and swallowed quite a few of them one winter night before she went to bed. She woke up the next morning, bright orange from head to toe, and her parents shoved her in the car and floored it to the nearest emergency room. When they walked in, the staff knew immediately what she had been up to, and that she was going to be OK and just don’t do this again. That product didn’t stay on the market very long. The only vitamin vegetarians need to worry about is B12 if you’re vegan, and your body stores up several years’ worth in the liver. There are some other conditions (hemochromatosis and Wilson’s disease are the first two that come to mind) where people have to be careful about mineral consumption, specifically iron and copper respectively, but anyone who’s posting here who has those conditions, or is at risk for them, probably knows that they do. People with kidney failure also have to be careful about their potassium and phosphorus intake. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [November 14, 2023, 2:59pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/11 "2023-11-14T14:59:50Z")
So do ruminants get it from their fermentation stomachs? You say fermented soy. Does that include soy sauce or only fermented tofu? ---
**Author:** ![Ulfreida](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ulfreida/32/8014_2.png) [@Ulfreida](https://boards.straightdope.com/u/Ulfreida)\ **Post date:** [November 14, 2023, 3:06pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/12 "2023-11-14T15:06:09Z")
Yes, they get it from the microflora in their stomachs. ---
**Author:** ![Ulfreida](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ulfreida/32/8014_2.png) [@Ulfreida](https://boards.straightdope.com/u/Ulfreida)\ **Post date:** [November 14, 2023, 3:30pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/13 "2023-11-14T15:30:32Z")
I’ve known many many vegetarians over decades and none of them have ever worried about _too many_ vitamins. It just isn’t a thing. But you can overeat certain families of vegetables which can interfere with vitamin absorption over time. That’s the opposite problem, readily solved by eating a wide variety in moderation. On the other hand,of course a typical American diet of meat, fat, and refined starches, with virtually no high-vitamin plants, is well known to be very unhealthy. Look into the “Mediterranean Diet”, which is the primary one that’s currently medically recommended as optimal: whole grains, vegetables, fruits, unrefined oils, and a modest amount of dairy and meat, avoiding smoked meats, red meat, and sugar. Also: insects are animals hence off limits to vegans. Accidental insects can’t be a significant source of anything. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 14, 2023, 9:16pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/14 "2023-11-14T21:16:12Z")
> [@Hari\_Seldon](#): > > You say fermented soy. Does that include soy sauce or only fermented tofu? None in soty sauce, some in tofu, which is a decent source. > [@Ulfreida](#): > > Also: insects are animals hence off limits to vegans. Accidental insects can’t be a significant source of anything. The average person accidentally consumes about a one pound of bugs per year, according to the US Department of Agriculture (USDA). Thats because fruits, vegetables, spices and many processed foods are legally permitted by the Food and Drug Administration (FDA) to contain tiny levels of bug parts, which add up over time. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [November 14, 2023, 9:28pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/15 "2023-11-14T21:28:05Z")
But do those tiny amounts of bugs add up to the needed amount of B12? There is probably no way of knowing, hence the practice of supplementing for this particular vitamin. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [November 14, 2023, 9:29pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/16 "2023-11-14T21:29:34Z")
Probably not. Which is why Vegan blogs etc suggest taking B12. ---
**Author:** ![Treppenwitz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treppenwitz/32/3445_2.png) [@Treppenwitz](https://boards.straightdope.com/u/Treppenwitz)\ **Post date:** [November 14, 2023, 10:05pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/17 "2023-11-14T22:05:26Z")
> [@Ulfreida](#): > > Look into the “Mediterranean Diet”, which is the primary one that’s currently medically recommended as optimal: whole grains, vegetables, fruits, unrefined oils, and a modest amount of dairy and meat, avoiding smoked meats, red meat, and sugar. I assume fish should be on the list? As I’ve observed before (in a rather whiny tone) _that’s almost exactly my diet_ - though not through choice (no red meat allowed). > [@DrDeth](#): > > Probably not. Which is why Vegan blogs etc suggest taking B12. I was thinking that some seaweeds are a source of B12 and did a little google. Here’s something I was unaware of (I think WebMD is trustworthy) > Nutritional yeast is a common source of vitamin B12 for vegans and vegetarians. People eat it as a go-to food that pairs well with a variety of other foods. And BTW > Seaweed is an alga rich in vitamin B12. It’s a common food in Asian countries. It’s a key ingredient of sushi and can be eaten separately as well. > > Eating 4 grams (g) of dried nori would meet your daily vitamin B12 needs. That’s a surprisingly small amount, I would say. [Source](https://www.webmd.com/diet/what-are-plant-food-sources-vitamin-b12) j ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [November 14, 2023, 10:15pm UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/18 "2023-11-14T22:15:30Z")
Third world vegans probably have enough weevil and insect contamination to provide the B-12 they need. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [November 15, 2023, 12:35am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/19 "2023-11-15T00:35:45Z")
If you can get B12 from yeast, what about bread? Actually vegemite is the way to go for yeast. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 15, 2023, 12:47am UTC](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084/20 "2023-11-15T00:47:47Z")
> [@snowthx](#): > > But do those tiny amounts of bugs add up to the needed amount of B12? There is probably no way of knowing, hence the practice of supplementing for this particular vitamin. Not in the First World, with our factory farms. But insect levels in food used to be a lot higher, even if you made a personal effort to avoid eating them. And you really don’t need very much B12. [Next page](https://boards.straightdope.com/t/do-vegans-vegetarians-have-to-do-vitamin-counting-to-make-sure-they-dont-overdose/993084.md?page=2)