B12 overdose / megadose?

[auntierozzi]

Today I received my blood test results and I have what seems like an enormously high level of B12. Normal range 145 - 180 pg/ml
My level is 239
Should I stop taking the Veg1 supplement do you think? I'm freaking out a bit because it seems that high B12 is associated with some illnesses.
Also my ferretin level has gone down from 50 ng/ml in the last year to 29 ng/ml Normal range between 15 - 160ng/ml.
I have called the Vegan Soc. who didn't have anybody who could give detailed advice. I would be so grateful if anybody could help me!! Thankyou.

[Michael Benis]

Korn you can have normal or high serum (blood) levels of B12 but low tissue levels (i.e. be deficient). This is, for example, common in alcoholics.

In other words, "normal" B12 blood levels do not always indicate a lack of B12 deficiency.

hth

Mike

[Korn]

Korn you can have normal or high serum (blood) levels of B12 but low tissue levels (i.e. be deficient).

Sure - my point was that if you overdose on B12, the body is capable of storing B12 - in the tissues.... but never mind. :)


In other words, "normal" B12 blood levels do not always indicate a lack of B12 deficiency.

Sure.

The last numbers I heard was that 50% of the people who have 'normal' B12 blood levels actually don't actually have sufficient levels of active B12 (this was a study on the average population, and not a vegan specific study).

[Michael Benis]

Well that's another point - suggesting apart form anything else that the word overdose may not be that appropriate....

[Korn]

I agree that nuances are important, 'megadose' is often a more relevant word than overdose, and there's also a huge difference between 'problems associated with overdose/megadose', 'allergic reactions', 'toxic reactions' or 'health problems associated with high B12 intake', or 'health problems associated with living on a diet with a higher amount of B12 than a vegan diet'...

As this thread grows longer, we probably should divide it into separate threads for overdose / generally high B12 intake / allergic reactions etc.

[Korn]

Today I received my blood test results and I have what seems like an enormously high level of B12. Normal range 145 - 180 pg/ml
My level is 239"

If you look at the references used in this (http://www.veganforum.com/forums/showthread.php?t=17684) new thread, you'll see that below 259 is considered the 'low normal range'...



Should I stop taking the Veg1 supplement do you think? I'm freaking out a bit because it seems that high B12 is associated with some illnesses.

If you read this thread only, it may seem that B12 overdosing is generally a more serious problem than not getting enough B12, but that's not the case - it's normally the other way round. I started this thread more or less as a comment to those who more or less assume we can never get too much B12... some of these take 100 times the needed B12 amounts daily - or more.

[Korn]

Here's something that looks like a perfect example of the kind of information we're not (http://www.3minutedepressioncure.com/index.php?kw=vitamin%20b12%20effects&nw=Content&pm=heartspring.net&sma=vitamin%20b12&s=S1G12C112A6T-1065408890) looking for. If you click on Free Instant Access" (no email needed), you'll find stuff like "I am out to help you cure your depression, once and for all, without using drugs like vitamin b12, which will undoubtedly turn you into a zombie". Why don't these salesmen get that people do not trust sites that claim that they can cure stuff in three minutes and sell audio CD's for $97? :)

[Korn]

There's a link between high amount of B12 and some types of cancer.
B12 is essential for growth and cell division.
Cancer =uncontrolled growth/cell division.
There's also a link between high intake of animal products and cancer (animal products generally contain more B12 than plants, which normally contain low or no B12).

Based on this info, and the assumption that too high levels of B12 both causes exaggerated growth (represented as body height) and exaggerated cell division / cell growth / cancer, I have assumed that there would be a link between body height and cancer.

After googling cancer and height, I found this:

http://www.bmj.com/cgi/content/full/317/7169/0/d

An association is known to exist between adult height and cancer mortality, but the reasons for this have been unclear. On p 1351 Davey Smith et al report on prospective observational data from the Whitehall study which confirms this association. They propose that dietary energy intake during growth may explain the increase in mortality with height. Pre-pubertal growth is largely due to increasing leg length, and Gunnell et al (p 1350) report a study of such data from the Boyd Orr cohort. They found that childhood leg length showed a significant positive association with mortality from non-smoking related cancers and suggest that both could be explained by changes in insulin-like growth factor concentration related to diet.

http://www.aicr.org/site/News2?abbr=pr_&page=NewsArticle&id=12899

“We found that tallness is also probably linked to increased risk for ovarian, pancreatic and pre-menopausal cancer as well,” said Willett. He was careful to note that, although the association between height and cancer is convincing, a tall person is not destined to get cancer.

Tallness is an indicator of risk, not a cause of it, Willett said. “If you’re tall, the Expert Report’s 10 Recommendations for Lowering Cancer Risk are even more important to you, not less.”

http://news.bbc.co.uk/1/hi/health/941890.stm

Height linked to breast cancer risk
A woman's height, as well as her weight, may be a factor in determining her risk of developing breast cancer.
Researchers in the Netherlands have been reviewing the data collected in seven major international research studies and have confirmed that taller women have a slightly increased risk of being diagnosed with breast cancer.

Scientists at Maastricht University looked at research involving 337,800 women, as well as 4,385 cases of invasive breast cancer.

They found that the risk of experiencing breast cancer increased by 7% with each 5cm increase in height for post-menopausal women, with a marginally increased risk among pre-menopausal women.

Reviewing results from previous cohort studies has also reinforced the link between weight and breast cancer risk, they reported in the American Journal of Epidemiology.

Women who are significantly overweight later in life are 26% more likely to develop breast cancer compared with those of average weight.

Paradoxically, however, being obese appears to have a protective effect in women before the menopause.

'Tall women should not be anxious'

Dr Tim Key, senior scientist at the Imperial Cancer Research Fund said the link between height and breast cancer risk had first been identified by comparing international statistics.

[Arabfrancophile]

I've taken B12 in the past because it helped my depression, then I stopped taking it about few months ago when I felt I was doing much better on my depression.

When I became a vegan I thought it might be a good idea to take it again.
So, I bought both Vegan One Multiple (100 mcg/ B12) and and Vegan B 12 ( 1000 mcg) from VegLife.

I've noticed that even when I took 1/2 of the B-12, in addition to the Veg-1 mutltiple, I got that feeling of tingling on my left arm and left leg. Then yesterday, I saw a bit of "acne like" on my face, just 2 or 3 spots.

Last night, I said to myself all of this must be just in my head and I took for the first time both the multiple and the whole B12 one, so I took about 1100 mcg. The tingling feelings on my left arm and my left leg was stronger and my heart start racing a bit.

Also, I forgot to mention that I've been eating lots of vitamin B-12 fortified vegan food. I was buying the ones with the highest B-12.

I don't remember going through side effects like these when I was taking B 12 for my depression but I know it was at much smaller dosage since I always looked for the smallest dosage possible when I bought my suplemnts.

Any how, I learned my lesson and from now on, I will take only 1/2 of the mutli one every other day and maybe 1/4 of the B 12 no more than once a week.

This thread has been very helpful for me.........peace, Mike :D

[Korn]

According to this (http://toxsci.oxfordjournals.org/cgi/content/abstract/18/3/389) article from 1992 about the effect of the effect of Folinic Acid, B6, and B12 on certain defects (the results are based on testing on mice. Sorry, mice.) "the dose levels should be carefully chosen since high doses of the combined vitamins can actually increase the incidence of certain defects".

[cobweb]

it's all rather confusing.............:undecided:

[Korn]

OK, here's the short version:
Too much or too little B12 seems to be a bad idea. For some years, some people have claimed that while too little B12 always is a problem, too much B12 isn't associated with any known problems. Many of the referred links in this thread suggests that the truth is a bit different...
:)

[cobweb]

i know, and thanks, but i'm still a bit confused - i take a mega b vit supplement so i'm not sure if i should be taking such a range of b vitamins or just b12, and how much.......

[Hemlock]

I've been taking a megadose for ages, got back from the doc who told me my B12 levels are 'excellent'. Now i don't know whether to keep taking it or switch to a lower dose:confused: Maybe it would help if I read the thread:)

[Korn]

How high was your megadose(s)?

A report from 1997 described children getting muscle twitching and/or seizure-like symptoms upon treatment with B12 in doses of 500 mcg or more. Other infants have developed tremors at doses of 300 mcg. Since you're not kids, cobweb and Hemlock, you should be able to handle more than that, but unless you have very special needs, I can't see why one would want to take B12 megadoses on a regular basis...

[Mike_]

Multivitamins didn't seem to cause it, but for a week I took a daily B12-only supplement bought in a pharmacy (250mcg of cyanocobalamin), and now I feel dizzy and nauseous. It's very annoying.

I've stopped the supplement a week ago but it persists.

Anyone had this? Help is appreciated.

Thanks.

[Mahk]

See a doctor. Your symptoms could be caused by any number of different reasons, many of which have nothing to do with being a vegan or what type of vitamins you take.

[Korn]

This thread is about overdoisng on B12, but here's some related info about possible side effects of taking cyanocobalamin:

http://www.answers.com/topic/vitamin-b12



Precautions

People who are sensitive to cobalamin or cobalt should not take cobalamin supplements. Symptoms of hypersensitivity may include swelling, itching, and shock. Adverse effects resulting from B12 supplementation are rare. Cobalamin should also be avoided by those who have a type of hereditary optic nerve atrophy known as Leber's disease.

Side Effects

Very high doses of cobalamin may sometimes cause acne.


Allergies

Vitamin B12 supplements should be avoided in people sensitive or allergic to cobalamin, cobalt, or any other product ingredients.


Side effects, contraindications, and warnings

Dermatologic: Itching, rash, transitory exanthema, and urticaria have been reported. Vitamin B12 (20 micrograms/day) and pyridoxine (80mg/day) has been associated with cases of rosacea fulminans, characterized by intense erythema with nodules, papules, and pustules. Symptoms may persist for up to 4 months after the supplement is stopped, and may require treatment with systemic corticosteroids and topical therapy.
Gastrointestinal: Diarrhea has been reported.
Hematologic: Peripheral vascular thrombosis has been reported. Treatment of vitamin B12 deficiency can unmask polycythemia vera, which is characterized by an increase in blood volume and the number of red blood cells. The correction of megaloblastic anemia with vitamin B12 can result in fatal hypokalemia and gout in susceptible individuals, and it can obscure folate deficiency in megaloblastic anemia. Caution is warranted.
Leber's disease: Vitamin B12 in the form of cyanocobalamin is contraindicated in early Leber's disease, which is hereditary optic nerve atrophy. Vitamin B12 can cause severe and swift optic atrophy.


There is no scientific evidence to support claims that cyanocobalamin can treat various other problems (such as allergies, mental problems, nerve disorders, skin problems). Treating yourself with large doses of cyanocobalamin can be unsafe. Do not treat yourself without your prescriber's advice.


What side effects may I notice from taking cyanocobalamin?

Serious side effects from cyanocobalamin are rare, but severe allergic reactions (progressing to fluid in the lungs or congestive heart failure) can occur. Side effects with cyanocobalamin include:
• chest tightness or pain
• difficulty breathing, wheezing or shortness of breath
• skin rash, redness and itching

Minor side effect with cyanocobalamin:
• diarrhea
Let your prescriber or health care professional know about this side effect if it does not go away.



As mentioned many times earlier, avoiding getting too little (and not too much) B12 is what normally needs focus...

[LuVegan15]

I get my b12 from Marmite. 60% of RDA per 4g serving. God knows I eat too much of it, haha.

[veganwitch]

I'm worried that my multivitamin may be providing too much B12. I searched until I found a vegan multi w/ the lowest dose of B12, but it is 100mcg which is 1666% of the RDA. The other thread about B12 excess being linked to prostate cancer raised my worries as my husband also takes this.

Maybe we should ditch the multi and just try to get B12 from fortified food?
Or maybe only take the multi occasionally? If so, how often should we take it.

Korn, your extent of research into the B12 issue and understanding of the issue is impressive. I would really appreciate your advice. Thanks.

[helen105281]

I take 1 fizzy B vit tablet a week. It does 666% RDA.

[veganwitch]

I was thinking of maybe only taking the multi once a week b/c of the b12, but then that would mean I wasn't getting the other vitamins in it on a daily basis. Idk, very confused.

[Korn]

Hi Veganwitch,

I can't really give any general advice (I don't even know if you need B12), but some people take a multi daily (if they need a multi) - preferably with very little B12 in it, and take B12 (eg. 9-10 mcg) as a separate supplement. You may not need either of these, or you may have very high or very low B12 levels, depending on what kind of food and supplements you have been taking the last few years. The problem is that your B12 needs vary based on a lot variables: coffee intake, stress, sugar consumption and a lot more, which is why I can't really give you any advice.

A little too much B12 is probably not a problem, but then again - all the articles that link high intake of animal products with various diseases could have to with a higher B12 intake, because a higher B12 intake is one of the things that is common for people who eat meat etc. (There's also animal proteins, fat and more). As we know, too little B12 definitely in't good either.

In general, if someone have had a high 12 intake for a while (from food or supplements) it could be a good idea to stay away from B12 for some time - unless, of course, they have a deficiency /absorption problem.

What is it that you think you need form those multis? Most multis contain B12, and the B12 found in multis are in various degrees inactive B12 analogues, which we don't seem to need (and which may even be harmful, although not so harmful as some people assume they are).

My best advice would be eat as healthy as possible, avoid as many nutrient killers as possible, and check your B12/MMA/homocysteine levels to check if you actually need therapeutic amounts of B12. Make sure having some fun while you're doing all of this. :-)

[veganwitch]

The problem is that your B12 needs vary based on a lot variables: coffee intake, stress, sugar consumption and a lot more

Hi Korn, thanks for your response. I'm going to do some research on what you mentioned above. I didn't realize that those things can affect B12 levels.



What is it that you think you need form those multis?

I'd been vegan for about 7 years w/ no supplementation. For the past couple of years I've been taking the multi that includes B12. I felt my eyesight deteriorating (meaning I probably could use glasses but wanted to avoid it) and I also live in mortal fear of breast cancer. So I was looking for vitamins that were good for eye health and breast health. Plus I had been experiencing extreme weakness in my upper arms. It was nearly impossible to raise them. I felt I was probably deficient in B12 and other vitamins. After I started the multi the arm weakness went away. Maybe it was a coincidence, idk.



My best advice would be eat as healthy as possible, avoid as many nutrient killers as possible, and check your B12/MMA/homocysteine levels to check if you actually need therapeutic amounts of B12. Make sure having some fun while you're doing all of this. :-)

Who wouldn't have fun doing all that? :rolleyes: I do try to eat healthy but I know I could do a lot better. When and if there is ever a blue moon and I find myself in a doctor's office letting them take blood, I'll have those levels checked. ;)

Again, thanks. I really appreciate your input :)

[Korn]

Hi again,

if you have been vegan for 7 years with no supplements, it's very unlikely that you have too high B12 levels, but it's a real chance that you'll have too low B12 levels (without supplementing) due the reasons discussed in this (http://www.veganforum.com/forums/showthread.php?t=196) and several other threads.

At some point in life (way earlier than most of us believe) people will experience will reduced eye sight, hearing abilities will be reduced over the years... - and so on. People who live on some special diet may as assume that whatever problems they have come from that diet (which they of course sometimes do), and forget than billions of people not living on any special diet also have health problems. But there's no reason no not do our best to avoid health problem - especially since an ill vegan easily could accused for being ill because he was a vegan, while an ill meat eater is 'just sick'. Remember that even among meat eaters, of which 50% also take some sort of supplements - low B12 levels are quite common (http://thyroid.about.com/cs/newsinfo/l/blb12anemia.htm), and the tests that document this don't even take MMA levels and homocysteine into consideration.



Who wouldn't have fun doing all that? :rolleyes: I do try to eat healthy but I know I could do a lot better. :-) Good luck in doing a lot better then! :-)