Page 1 of 1

B12 supplement questions

Posted: Wed Jul 10, 2019 11:36 am
by ishmael
Sorry in advance if this post is all over the place. I've been doing a lot of googling and still can't seem to find exactly the information I'm looking for so I was hoping I could ask this here. If I'm mistaken or there's already a thread answering this (I did a small search and scrolled through a few pages) please let me know. Here is a page that has most of the information I've seen scattered across the internet in one place: ... sional/#h2

I've read that the recommended daily allowance of B12 for adults is 2.4mcg. Somewhere on that page it said that the average amount people get is actually a little higher, but that it's harder for vegans/vegetarians to get B12 (sorry for boring you guys, I know B12 is old hat). It also says that "only about 10 mcg of a 500 mcg oral supplement is actually absorbed in healthy people." What I want to understand is why all of the B12 supplements I see in stores offer well over 100% of the suggested daily amount? For example, that 500mcg supplement would offer over 400%, right? (I'm not the greatest at math, sorry.)

My problem is that every time I take my B12 supplement (which is meant to be daily, according to the suggested use) I get so nauseous that sometimes I vomit. Granted, mine is 5,000mcg (quick dissolve) because I am an idiot and when I needed to buy more after my last bottle ran out I looked at all of them on the shelf and thought "oh, this one has 5,000mcg compared to 1,000mcg for the same price?? Obviously I will buy the 5,000mcg" without understanding anything about what my body actually needs. I can't find much about people getting sick after taking a B12 supplement, just the effects of deficiency. And to be honest I don't know that I'm deficient, I'm just assuming that because I was vegetarian for 9 years and have been vegan for about 1.5 I must need a supplement as it's what all the research shows. I realize now, or I suspect, that obviously the 5,000mcg is for someone with quite a deficiency, right?

What I ultimately want to know is what dose of a B12 supplement should I actually be taking? What dose do other vegans take? Do I need to get blood work done to determine this sort of thing? Over the years I don't recall ever having been told by a doctor that I'm deficient in anything but I don't eat a super well planned out diet (lots of vegetables, fruits, cooked chickpeas, soy yogurt, etc). I've been considering seeing a nutritionist (for increased severity and frequency of migraines/headaches) but before I spend the money I wanted to get an idea of where I'm at on certain things that I've supplemented in the past and try to adjust my diet on my own. B12 is one of my concerns as it's highly recommended for a healthy vegan lifestyle, as is also protein (I have so many questions about how much we actually need to be eating but I guess that's another topic).

Also, if someone can recommend a vegan B12 I would appreciate it as opposed to just googling and reading random, potentially monetized recommendations. While checking the label of my current B12 (which I already planned to stop using on account of its extremely high dose and, you know, the vomiting) for possible allergens I noticed that there's actually a couple ingredients which probably aren't vegan. If anyone wants to critique or suggest some ingredient, as opposed to just the high dose, that's making me sick the full list is as follows: mannitol, crospovidone, microcrystalline cellulose, contains 2% or less cyanocobalamin (should this not be the first ingredient?), hydrogenated vegetable oil, magnesium stearate, natural cherry flavor, stearic acid, sucralose. I'm assuming the stearic acid/magnesium stearate is from animal sources or they likely would have specified it's from vegetable sources.

Also also, I just received the deva vegan multivitamin in the mail, which I see recommended a lot on here :) I am excited to start taking it! I hope I don't come off as a total dingus in this post, I'm trying to take responsibility for my own ignorance and lack of education about these things.

Thanks in advance if anyone is willing to give me some tips or insight!

Re: B12 supplement questions

Posted: Wed Jul 10, 2019 7:23 pm
by EquALLity
Interesting that you posted this, beacuse I just started taking vitamin B12 again. I never took it consistently and have been vegan for 5.5 years. :lol: Awhile ago, I had bloodwork done, and the doctor said I was slightly deficient and B12 and should probably supplement since I'm vegan. Even though B12 isn't in many vegan foods, it can be stored in your liver for years, and I think this is why I wasn't very deficient.

As to your question, I think that supplements often have higher amounts of vitamins than is necessary because people typically take them when they suspect that they or already are deficient, and they are trying to quickly fix deficiency. A few years ago, I was deficient in vitamin D, and a doctor prescribed me an extremely high amount of vitamin D, even though over-the-counter vitamin D is already above the recommended daily value. Presumably, she was trying to help me correct the deficiency as quickly as possible. I would guess that the over-the-counter supplements apply the same logic.

I think you should just see what works for your body. If you don't notice any adverse effects of taking 1000 mcg of B12 daily, then you can keep taking it. Eventually, you can get a blood test and see if you're at a healthy rate, which you probably would be. Then, you could keep taking 1000 mcg and take another test later. If you are stable, then you should continue, and if not, cut it to whatever the appropriate rate would be based on the difference in the tests.

Instead of actually testing it, I'm probably going to just take 1000 mcg for a long time and then start taking it less and less, so that I'm eventually just taking the required amount. I don't think you have to test it unless you believe you are extremely deficient and may need to take urgent action.

Re: B12 supplement questions

Posted: Thu Jul 11, 2019 3:25 pm
by Lay Vegan
Hi Ishmael,

You can check out ‪‬ or the veganrd for evidence-based nutrition advice on this. Figuring out appropriate dosage of B12 can be difficult because of the way it’s absorbed by the body. Vegans typically take a vitamin because it’s convenient, but getting all of it at once through the source of a single tablet means we need a much larger dose. The RDA for B12 is 2.4 mcg, but dietitians recommend taking a daily supplement of 25-100 mcg or taking a supplement of 1,000 mcg twice a week. The deva multivitamin you indicated you’re taking works fine.

Please note that if you’re taking B12 in the form of methylcobalamin, you’ll need to take even higher doses to avoid deficiency.

In the meantime, I would not recommend that you stop supplementing altogether until your blood tests “confirm” a low level. Routine blood tests often do not adequately measure for B12 levels, and a test that shows a serum B12 level of within the normal range doesn’t necessarily ensure that levels or healthy. Supplements are safe, cheap, and effective! By all means, if you’re concerned that you’re at risk of deficiency or your health is declining please consult your doctor or dietitian.

Good luck

Re: B12 supplement questions

Posted: Sat Jul 13, 2019 4:34 am
by brimstoneSalad
Good questions!

We have a section in nutrients of concern on B-12, it's fairly comprehensive... and probably more info than you ever wanted to know on B-12:

As to the absorption thing, it's a matter of diminishing returns.
If you take a tiny bit, you absorb all of it, if you take a huge amount, you absorb way less by percentage, and only slightly more than taking a small dose.

The recommended amount for vegans is about 100 mcg a day for a single dose, but even 1,000 shouldn't hurt you as long as you're not a smoker.
If you smoke, just 25 mcg a day may be better.

You can use your current supplements. The stearic acid is very unlikely to be animal derived, even though they didn't mention if it was plant or animal (the probably don't even know, but most sources are going to be plant based).
I suggest you cut them up. You can quarter them and take them that way, or even try to cut them again into 1/8ths. That should help resolve the nausea. And you can take it with food and water, which may help more.

The DEVA multi is good, glad you were able to order it. But if you haven't taken B-12 in a while you should probably keep on with your B-12 supplements too for a little while to make sure your levels are good.

Please don't hesitate to ask if you have any more questions.

Re: B12 supplement questions

Posted: Sat Jul 13, 2019 10:04 am
by ishmael
Thank you for the replies!


I appreciate your advice! I feel like it makes sense in general. I've taken a variety of supplements over the years mostly just because my mom recommended them (she's not a doctor or nutritionist, lol, also I am a grown adult :?). So I started taking things like B12 almost 10 years ago but not consistently, like you mentioned. I would take the B12 for a couple months, missing a day or two, then go off of it and my other supplements for months at a time. Maybe if I had taken B12 daily for 10 years I wouldn't get sick from this high dose? But as it shouldn't harm me I will try to continue and supplement in smaller doses until I find one that doesn't make me nauseous.

Lay Vegan

I've read (or watched, it might have been an Unnatural Vegan video?) about the argument for methylcobalamin by some and feel comfortable continuing to take cyano. However, I tried talking to my aforementioned mother who has been recommending me supplements all these years about my B12 concerns and she sent me a picture she took of this book she has where the author recommends methyl. I googled it and cringed because I realized she's been following his ideas for almost a year (Steven Gundry, the book is called The Plant Paradox). She tried to get me to take these pills that were supposed to stop me from absorbing lectins and was really sure I needed them because I eat so many vegetables. I wouldn't do it because the capsules contained gelatin and wow I'm glad I finally started to question her suggestions because if this guy is basically panned as a spreader of pseudoscience then what else has she been reading? I should've known all those years ago when she started watching Dr. Oz :roll: Fortunately the majority of the supplements she's recommended have been harmless (I think) but now I'm going to google every one before taking them again.

As an aside, I tried searching the forum for any mention of "Gundry" and nothing came up. Does this mean he's so widely accepted as a dingus that vegans don't even acknowledge him?


I didn't realize there was a wiki! Every question I have now or in the future can probably be answered there, jeez. Thank you!

And thanks for your insight on the ingredients and your suggestions for at least using up the bottle I have. I try to always take my supplements with food but I still always got nauseous. Since I took several supplements (maybe like 5: B12, zinc, vitamin C, spirulina, and olive leaf extract [don't even remember why my mom wanted me to take the latter two and I'm starting to feel like a real idiot for not doing my own research all these years]) with my lunch before going to work I kind of just assumed I was taking too many in one sitting? Also I tend to get car sick, and I hate my job, so maybe I was psyching myself out? But I got so violently nauseous one day recently when all I had taken was the B12 and realized that must be the culprit. I will try cutting a tablet down as far as I can manage and see how I do with the smaller doses!

Re: B12 supplement questions

Posted: Mon Jul 15, 2019 2:09 am
by brimstoneSalad
ishmael wrote:
Sat Jul 13, 2019 10:04 am
I didn't realize there was a wiki! Every question I have now or in the future can probably be answered there, jeez. Thank you!
Hopefully some day, but right now it's pretty incomplete. That just happens to be one of the few more fleshed out areas.

Let us know how it goes!