B-Vitamin Complex pills and RDA's

[RachelJune]

I've recently started taking a daily B-Vitamin Complex pill. I only noticed today that the RDA's on the back of the container seem ridiculously high, e.g. 1000%. Is this safe?

On a more personal note, I have noticed when I go to the loo my wee is now a luminous bright yellow colour Is this anything to do with the supplements? And if so, is it normal? I wondered if perhaps it might be my body getting rid of any excess vitamins, given that the content of each pill is so high... On the other hand, I've been told I'm deficient in certain B vitamins, including B12, so surely my body shouldn't be complaining now it's getting some?

I'm afraid I'm not too knowledgeable on this sort of thing, so any advice would be much appreciated.

[harpy]

I seem to remember reading that one does excrete any unneeded vitamin B12 (at least) but I haven't heard the thing about luminous wee before

The RDA for vitamin B12 is supposed to be right for preventing nerve damage but possibly too low for other purposes (you need B12+folic acid to keep homocysteine levels down according to one theory). There's a lot of stuff about this on the Vegan Society web site although I think it's still open to debate.

How are you feeling since you started taking the supplement - OK?

[Korn]

I've recently started taking a daily B-Vitamin Complex pill. I only noticed today that the RDA's on the back of the container seem ridiculously high, e.g. 1000%. Is this safe?

You have very valid reason to be confused about RDAs, because the answer you get depends on who you ask.

(Jump to the last paragraph if you want a short answer! )

Here's what The Vegan Society writes:

The only reliable vegan sources of B12 are foods fortified with B12 (including some plant milks, some soy products and some breakfast cereals) and B12 supplements.

This is confusing for several reasons - they don't comment B12 levels in plants (most plants haven't been tested for B12), they don't dive into the B12 analogues issue at all (B12 may also contain B12 analogues). I would rather have phrased in a way that tells people that for a number of reasons, people (meat eaters included) may have low levels of B12 even if you eat a balanced, varied diet.

Vitamin B12, whether in supplements, fortified foods, or animal products, comes from micro-organisms.

I would have added something about synthesizing the B12 molecule here, but I guess they just want to debunk the myth that B12 comes from animals - amyth that's important to debunk!

Most vegans consume enough B12 to avoid anaemia and nervous system damage, but many do not get enough to minimise potential risk of heart disease or pregnancy complications.

Much of what is written about B12 and vegans seems to somewhat have been based on an assumption that there's no disagreement about the link between B12 and homocysteine. A discussion about homocysteine and B12 has been going on for years. This last sentence is also confusing, because: how can vegans get enough B12 to avoid anemia and nervous system damage if there are no reliable vegan sources of B12?


THe known anti-vegan Victor Herbert himself wrote a while ago that 'the minimum daily requirement (MDR) for vitamin B12 to sustain normality is probably in the range of of ~0.1 mcg. 0.2-0.25 mcg absorbed daily from food is probably adequate for anybody". This is much less than 1 microgram, but since not all B12 is absorbed, and a lot B12 is killed, most people recommend that we get more, up to circa 1.5-3 mcg daily.

In the same article, 'Vitamin B12, sources and requirements', he also writes that 'We (the 1980-85 RDA Committee) reduced the RDA for vitamin B12 to 2mcg for adults (which is still more than more than anybody needs) because there was no scientific basis for higher amounts. As delineated above, nobody needs that much, there is no evidence that it has any value whatsoever for humans and, as we discover more and more about the excess of any nutrient, we discover harms we did not know existed. It will probably turn out eventually that too much vitamin B12, like too much of everything, is harmful".

Now, 20 years later, most people agree that 1.5-3 mcg daily is a healty recommended daily intake. The Vegan Society writes:

To get the full benefit of a vegan diet, vegans should do one of the following:

eat fortified foods two or three times a day to get at least three micrograms (µg or mcg) of B12 a day

Then they write:

or take one B12 supplement daily providing at least 10 micrograms

This is getting more confusing, because shouldn't B12 from supplements/fortified foods be easier to absorb that B12 from real food... why do we need 10 mcg when 2-3 is consider enough by most others? Good question. I think what they write is based on the assumption that too much B12 isn't a real problem, and the fact that if you consume all your B12 in one pill (eg. 10 mcg), you'll consume less B12 than of you divide that pill in 5 parts and eat 2 mcg five times a day. Does this mean that The Vegan Society is right and that the millions of supplements meant to be taken once a day are not strong enough? Well, ask TVS... And read something about homocysteine.

Then Thee Vegan Society writes:

or take a weekly B12 supplement providing at least 2000 micrograms

Wait... how can we need 2000 mcg a week, if less than 3 mcg daily (maybe a lot less) is actually needed? Here's what they write:

Homocysteine rises significantly long before B12 stores drop to the level associated with classical B12 deficiency. Current UK Government recommendations of 1.5 µg per day are based on reliably preventing classical deficiency and are more than adequate for that purpose. However, they do not take into account B12 requirements to minimise homocysteine. At least 3 µg per day are required to achieve this by maintaining blood B12 levels at 300 pmol/l or more. If the main source of B12 is a supplement taken daily, at least 10 µg should be taken. If it is taken weekly, 2000 µg is required. The variation in recommended weekly intake is because absorption of B12 is best at small doses below 0.5 µg, where about 70% of available B12 is absorbed. As the dose approaches 10 µg, the amount absorbed flattens off at about 1.5 µg and only about 0.5% of further increases in dose are absorbed. The absorbed amount from 2000 µg is therefore little more than 10 µg, which is just enough for one week, while the same absorbed amount can be obtained from 3 µg per day spread across several meals or from a daily supplement of 10 µg.

So much about their recommendations - and why some B12 supplements contain a lot more than the RDA. Back to your question: With a RDA @ 1.5 mcg, 1000% of the RDA would mean 15 mcg, which definitely is more than you'd normally need. But if you are deficient, you need more than a non-deficient person until you are not deficient anymore, and the whole thing is confusing because not only do the daily recommendations vary from country to country, but they also vary depending on who you ask... eg. lots people would say that a daily supplement as strong as 10 mcg wouldn't be needed at all, selling 10 mcg B12 pills is even illegal some places (without prescription). The definition of B12 deficient is also vague, and the amount of B12 you need to consume depends on how many B12 'enemies' you are exposed to...

I've probably only added confusion now - sorry! - but this whole thing is both complex and confusing. Depending on how B12 deficient you are, and dependent whether these pills are meant to be taken only once pr. day or not, and how much B12 they actually contain, what kind of B12 they contain, it would have been easier to say something useful...

To reduce the confusion a bit, let me add that (in spite of some discussion about B12 overdosing) most experts would say that taking eg. 15 mcg cobalamin daily for a B12 deficient person would represent any health risks at all. They'd probably say that it would represent a health risk not to take extra B12 until your deficiency was gone.


(We also have this thread: At what levels is B12 absorption best?)

[Gorilla]

Hi Rachel,

i'm not an expert on the subject by any means, but i can tell you that i took a high-dose B-vitamin supplement for a while and it made my wee bright yellow too so i guess it's a common side-effect. it went back to normal when i stopped taking the supplements.

i don't know if i was deficient in any of these vitamins but i was taking them to supposedly help depression, it didn't seem to make any difference though and i was a bit worried about the excessive doses in the supplement.

[RedWellies]

I have noticed when I go to the loo my wee is now a luminous bright yellow colour Is this anything to do with the supplements? And if so, is it normal?

Mine did the same when I took supplements over the w/e (they were B vits, including B12) so I guess it's normal. If you Google, thoughts are that it's the excess vits being excreted. Did it take your wee long to go yellow? Mine turned very quickly, within hours.

As for the high doses, maybe don't take it every day? I took mine over the w/e (Fri, Sat and Sun) but haven't had one since. I'm experimenting to see if my tingling arms and legs are related.

[RachelJune]

Thanks guys. That's really helpful

Korn, the tablets I'm taking are Natures Aid Health Products "Mega Vitamin B Complex 100 (Time Release)". Instructions are to take 1 tablet per day with food, and each tablet provides the following:

Vitamin C 30 mg 50%
B1 100 mg 7143%
B2 100 mg 6250%
B3 100 mg 556%
B6 100 mg 5000%
Folic Acid 400 ug 200%
B12 100 ug 10000%
Biotin 100 ug 67%
B5 100 mg 1667%
Choline Bitartrate 100 mg ---
Inositol 100 mg ---
PABA 30 mg ---

I've only been taking them for a week now. I don't feel any different yet, to be honest, but then I wouldn't really be expecting anything in such a short time. I have a month's supply so I'll see how it goes

It's good to know I'm not the only one to notice the wee thing! I too noticed it within a day of starting taking them.

[Gorilla]

I'm experimenting to see if my tingling arms and legs are related.

is that because you think you might be low in B12? the thing is, if your B-vitamin supplement has a high level of B6 in it, that can itself cause tingling or numbness apparently. so you may be increasing your B12 levels but it may not produce any noticeable improvement if the B6 is counteracting it (as far as the tingling is concerned).

[RedWellies]

is that because you think you might be low in B12?

I wondered if I might be. I had the tingling before taking the supplements.