Tag: vitamin B12

Greater need for vitamin B-12

Claus Hancke

February 1, 2006

Middle-aged and elderly women’s need for Vitamin B-12 is with great certainty 2,5 times higher than previously believed. A daily vitamin tablet is often not enough.

How is the need for a vitamin determined? Earlier it was determined based on how much is necessary to avoid acute deficiencies. This is sometimes still the case. For example, the current recommendations for vitamin C are still based on a World War II study on 20 English military objectors. Half of them came down with scurvy and two were close to death. But this study found that scurvy can be avoided with 12 mg vitamin C per day.

This kind of research is brutal by today’s standards. But it is also antiquated because it does not take other deficiency symptoms into account, including those which arise after longer periods and are not coupled with bruising of the skin, brittle bones, paralyses, and other acute symptoms. Today, instead of merely recording with a study participant becomes deathly ill, we follow the processes that the vitamins in question are involved in and determine whether or not they function as they should. This methodology was used by the American, Mark Levine when he proved that our need for vitamin C is closed to 200 mg per day than the normally recommended 60 mg. If one makes due with 60 mg it is believed that the vitamin C dependant reactions become slow and that there is an significantly increased risk of cardiovascular disease and cancer.

Of current interest, there is news regarding the need for vitamin B12. The current recommendation in England has been set to 1 microgram per day. A Danish study has recently shown that the need for vitamin B12 is six times as much (6 micrograms). This was determined in a study of 98 Danish women with an average age of 60. Such a large need meanwhile created a problem; the women typically only received 4.6 micrograms via their diet.

Even though they supplemented their intake with a normal vitamin pill (1 microgram B12), half of them received too little vitamin B12. Stronger pills are needed.

Increasing recommendations
For the last 50 years B12 status has been determined by measuring the blood’s B12 content. Findings in recent years have shown that a “normal” B12 value does not necessarily mean that there is enough. Even with a normal B12 value, build op of metabolism products which B12 normally removes can occur (these include homocysteine and MMA, otherwise known as methylmalonic acid). Therefore the amount of these substances present is measured when trying to determine whether or not there is a deficiency.

Recently a third indirect measure for B12 deficiency has been put into focus: holotranscobalamin, a B12 containing protein, seems to be able to replace the above-mentioned method and may even be more sensitive to B12 deficiency. It is very important to get enough of this protein. It is responsible for delivering B12 to the cells, almost like the paperboy who delivers the paper to your door. Without the paperboy, there is no paper.

The Danish study showed that the values for Holotranscobalamin, MMA, and homocysteine no longer indicated deficiency only when a B12 intake of over 6 micrograms per day was achieved. If B12 intake is less than 6 micrograms, there is sand in the B12-works.

The researchers conclude with conviction:
”…our results, together with those of others, strongly suggest that the RDA of 2.4 micrograms/day should be increased.”
This can also been said about many other vitamins. Experience from recent years indicates that the recommendations for not only vitamin B12, but also vitamins C and E and the minerals selenium, chromium, and magnesium, should also be increased, and in some cases greatly increased. Increased intake of many of the other B vitamins as well as iodine should also be considered.

This is especially true about vitamin D, on which we at the Danish Vitality Counsel have focused. The recommended daily dosage of vitamin D should be doubled for those of us who live in northern climes.

The official recommendations have as a whole not followed developments in research, even though there are strong arguments for new recommendations. According to some, there is need for more evidence. But this is contrary to the supposition that new recommendations could prevent serious chronic disease.

The dilemma is strengthened by the fact that it is difficult or impossible to get higher doses of vitamins and minerals though our modern diet. Some suggest that it might be possible with a Stone Age diet, but we surely will not have another Stone Age.

By: Vitality Council

References:
1. Mustafa Vakar Bor et al. A daily intake of approximately 6 {micro}g vitamin B-12 appears to saturate all the vitamin B-12-related variables in Danish postmenopausal women. Am J Clin Nutr. 2006 Jan;83(1):52-8.
2. Zouë Lloyd-Wright et al. Holotranscobalamin as an Indicator of Dietary Vitamin B12 Deficiency. Clinical Chemistry 49: 2076-2078, 2003;10.1373/clinchem.2003.020743.

www.ajcn.org
www.clinchem.org
www.iom.dk

Vitamin B12 And Folic Acid Reduce The Risk Of Blood Clots In The Brain

Claus Hancke

October 31, 2005

After Americans enriched their diet with folic acid in 1996, the frequency of blood clots in the brain was reduced by 15%. Now research shows that added supplementation of Vitamin B12 will markedly lower this risk even further.

Immediately, it sounds simple: People with high levels of the amino acid homocysteine in the blood have an increased risk of blood clots in the brain and in the heart. You also know that you can lower homocysteine with folic acid and, to a lesser extent, with B6 and B12 vitamins. When the Americans began to enrich cereal products with folic acid from 1996, both the average American’s homocysteine and the rate of blood clot in the brain decreased by about 15% in three years.

“The money fits”, and then the result is almost obvious in advance, if you want to conduct a lottery experiment, where every other participant gets folic acid, B6 and B12 vitamins. Of course, they get fewer blood clots in the brain.

But the reality is more varied. In Norway, such an experiment (NORVIT) was conducted with 3,750 patients who had just survived a blood clot in the heart. For 3.5 years, they were supplemented with either folic acid (0.8 mg), vitamin B6 (40 mg), both or blind tablets (placebo). Among those who only received folic acid, mortality decreased approx. 10%, but not statistically certain. But in the other two groups the death tolls were increased, not statistically certain either.

Perhaps it is too late to start taking supplements when you are already severely calcified. Or, as will appear, perhaps it was more decisive that the Norwegians “forgot” to give the participants vitamin B12.

An experiment has also been carried out in the USA (VISP). It was with people who had recovered from a blood clot in the brain, but had an increased risk of a new one. Admittedly, the Americans did not initially find any effect either. Supplementation of folic acid (2.5 mg), vitamin B6 (25 mg) and vitamin B12 (0.4 mg) did not reduce or improve mortality or risk of blood clots in the brain. Therefore, the experiment was simply stopped after two years. It was useless, they thought.

B12 is useful if it is absorbed
A close explanation could be the aforementioned enrichment of cereal products with folic acid. After all, the average homocysteine had already fallen by approx. 15% in the Americans. During the trial, it only dropped a further 2%.

But the Americans have since studied the numbers more closely. In doing so, they discovered one important source of error in particular: Many of the 3,680 elderly participants had reduced absorption of vitamin B12 from the gut and therefore had relatively little B12 in their blood (less than 250 pmol/l). This is often seen in the elderly, and it is now known that these elderly need supplements of at least 1,000 micrograms of vitamin B12 per day. But the participants had only received 400.

What would it look like if you now disregarded these participants and concentrated on those with normal B12 uptake? It was decided to investigate. At the same time, participants with reduced kidney function were disregarded, as they also respond sluggishly to these supplements. Finally, participants who were previously receiving medical treatment with B12 were naturally disregarded.

There remained 2,155 people who had no problems absorbing B12. In this large group, the supplements both lowered homocysteine further and reduced the overall risk of death, blood clot in the heart or blood clot in the brain – by 21%! The treatment helped anyway; even a lot when the ability to absorb B12 was intact.

As stated, it appears that the fortification of cereal products with folic acid has reduced the Americans’ risk of blood clots in the brain by approx. 15%. Now it seems that a solid supplement of vitamin B12 on top of that can reduce it significantly more – but the many elderly people, who absorb vitamin B12 poorly, presumably need larger supplements.

This is the result at the moment. It must be verified before it is approved. But the indications are there.

By: Vitality Council

References:
1. Toole JF, et al. Lowering homocysteine in patients with ischemic stroke to prevent recurrent stroke, myocardial infarction, and death: the Vitamin Intervention for Stroke Prevention (VISP) randomized controlled trial. JAMA. 2004 Feb 4;291(5):565-75.
2. Bonaa KH. NORVIT: Randomized trial of homocysteine-lowering with B-vitamins for secondary prevention of cardiovascular disease after acute myocardial infarction. Program and Abstracts from the European Society of Cardiology Congress 2005; September 3-7, 2005; Stockholm, Sweden. Hot Line II. Iflg. Linda Brooks. NORVIT: The norwegian vitamin trial. Medscape sept. 2005. (Ikke publiceret i trykt medie)
3. Spence DJ et al. Vitamin intervention for stroke prevention trial. An efficacy analysis. Stroke 2005;36:2404-2409.

jama.ama-assn.org
www.medscape.com
stroke.ahajournals.org
www.iom.dk

You Must Plug The Hole Before The Boat Sinks

Claus Hancke

October 11, 2005

A Norwegian study has shown that if you have already experienced an acute myocardial infarction, the risk of another such infarction will not be reduced by taking folic acid, Vitamin B6, and Vitamin B12, even if homocysteine levels are lowered thereby.
If you get a great deal of folic acid, the blood content of the amino acid homocysteine will be relatively low. So much is certain. When the content is low, the risk of blood clots in the heart or brain hemorrrhage – other things being equal – is also low. It is also safe, but both are statistics only.

With these facts in the bag, one is tempted to think that supplementation with folic acid must be a good idea. As you know, folic acid is the B vitamin that young women should take to avoid having children with spina bifida. One can agree with the American Heart Association, which advises everyone to get 0.4 mg of folic acid a day, the same dose that women should take as a supplement.

In Tromsø in Norway, the so-called NORVIT trial (Norwegian Vitamin Trial) was the first to test whether supplements also help heart patients who have already had a blood clot in the heart. If the media is to be believed, it ended with a scare.

The results, which were presented in September at this year’s congress of the European Society of Cardiology (ESC), led directly to warnings against folic acid in the press: B vitamins could be dangerous for heart patients, it said, and our own Danish heart association was quick to announce, that folic acid is “still” not recommended for heart patients – even though the month before was said something close to the opposite.

But, as is so often the case, the reports were misleading. Strictly speaking, the Norwegian trial did not show that folic acid is dangerous. If you want to argue that it showed anything at all, it was that the risk of heart attack, stroke, or death decreased—albeit by only a few percent—in those who took 0.8 milligrams of folic acid a day for 3.5 years . However, this was not statistically certain.

The fact is that there were in fact not one, but three trials, with a total of 3,750 people, all of whom had had blood clots in the heart. One showed that a combination of folic acid, vitamin B6 and B12 led to approx. 20% more cases of blood clots in the heart than placebo (cheat pills). The second – the only one where only folic acid was used – showed no difference in reality. There was also no difference in the third trial, where the participants only received vitamin B6.

In one area, the experiments turned out to be successful: those who received folic acid achieved a drop in the blood homocysteine content of approx. 30%. Enough so that one could hope for a nice drop in the number of new blood clots. Which did not appear.

But the questions arise: Is it appropriate for heart patients to be careful about taking folic acid, vitamin B6 and vitamin B12 at the same time?
Or are we talking about completely different anatomical conditions with secondary prophylaxis than there are with primary prophylaxis? After all, you have had a blood clot.

Also at the congress, the ESC’s designated commentator, Ian Graham, doubted the result. He believed that the experiment might have been too small and too complicated to be credible.

One can go a step further and think that the result is purely due to chance. In any case, it is not supported by any theory.
It is more likely that folic acid is simply not suitable for preventing blood clots in severely arteriosclerotic patients. – In other words secondary prophylaxis.

There is a lot of evidence that folic acid – and low homocysteine – slows the development of atherosclerosis in healthy people – i.e. primary prophylaxis. But the usefulness of this function diminishes when the calcification is already very advanced. The bottom plug must be inserted before the boat is sunk.

If folic acid is to prevent blood clots, you probably have to start in good time. On the other hand, the vitamin has other benefits. Among other things. experiments convincingly indicate that it helps to keep the brain young, even in the elderly.

By: Vitality Council

Reference:
Bonaa KH. NORVIT: Randomized trial of homocysteine-lowering with B-vitamins for secondary prevention of cardiovascular disease after acute myocardial infarction. Program and Abstracts from the European Society of Cardiology Congress 2005; September 3-7, 2005; Stockholm, Sweden. Hot Line II. Iflg. Linda Brooks. NORVIT: The Norwegian vitamin trial. Medscape Sept. 2005. (Not published in a printed media).

www.medscape.com/viewprogram/4494_pnt
www.iom.dk

Deficiency in B-vitamin Causes Dementia

Claus Hancke

April 18, 2005

According to one American study, folic acid weakens the memory of the elderly. According to another study, the opposite happens. Nearly all studies, however, indirectly indicate that folic acid prevents both arteriosclerosis and dementia.

It is a well-known fact that the B-vitamin folic acid prevents congenital neural tube defects. However, it can also lower the blood’s content of homocysteine; a biproduct in human metabolism that promotes atherosclerosis, among other things. Having an increased level of homocysteine is just as dangerous as cholesterol: Up to 40% of all individuals with premature atherosclerosis have increased blood levels of homocysteine.

The fact that homocysteine also damages the brain is indicated by more than 20 different studies. It has been found with almost unerring certainty that demented old people have more homocysteine in their blood than others and that the ones who score highest on memory tests are the ones with the least homocysteine in their blood. This is a clear argument for taking folic acid.

However, completely unexpectedly, a fly in the ointment has now appeared. A study at Rush University in Chicago has shown that the exact opposite might be the case. If you are elderly and you get more than the typical 0.4mg. of folic acid a day, your memory will decline more rapidly.

A total of 3,718 trial subjects over 65 years of age were followed for five to six years after having reported their eating habits. They were then mentally tested three times during the course of the 5 – 6 years. The results were the same whether they got folic acid from their diet or from dietary supplements: In the people taking folic acid, memory declined more rapidly than in the others.

Are these results the result of a coincidence? Anyhow, it does make you wonder that the 20% who got the most folic acid (0.7 mg. a day) did far better on the mental tests than the rest. Granted, their memory deteriorated more rapidly, but they obviously had a better memory to begin with. Why was that so, if folic acid is actually harmful?

In addition to this, doctors from the UCLA in February 2005 published results stating the exact opposite. Among 499 well-functioning 70 – 79 year-olds, most folic acid was found in the blood of the ones who had the best memory. And equally importantly: Seven years later, they were in better posession of all their faculties.

No explanation
What is true, then? If the truth lies in the Chicago study, it might be based on the co-operation between vitamin B12 and folic acid. Both vitamins reduce blood levels of homocysteine and the major task of both of them is to produce small, chemical units – which only contain a single carbon atom – for building other molecules.

Folic acid delivers its units to vitamin B12 which are then further delivered to – homocysteine. In this way, homocysteine is neutralized and is transformed into a harmless amino acid and the blood level of homocysteine will drop.

Whether you lack vitamin B12, folic acid, or both, the transport of the single-carbon units will be complicated. In all three cases, the result will be a specific type of anaemia (pernicious anaemia) which is characterized by the red blood cells being abnormally large.

However, the symptoms in vitamin B12 deficiency and folic acid deficiency are not quite similar. In folic acid deficiency, neuritis – i.e. nerve damage – will not occur. In vitamin B12 deficiency, it will. The anaemia in vitamin B12 deficiency can be removed by taking folic acid, but the neuritis cannot. Vitamin B12 has an affect on nervous tissue that folic acid cannot imitate.

In up to 30% of all elderly people, vitamin B12 deficiency can be demonstrated. Imagine large amounts of folic acid enhancing the B12 deficiency in the nervous system by blocking the small amounts of vitamin B12 with single-carbon compounds. This could correlate to another finding in the Chicago study: Memory declined by 25% less in the ones with the largest consumption of vitamin B12.

The leader of the study, Martha Clare Morris, believes that folic acid might mask the very common vitamin B12 deficiency in the elderly. This is more or less the same thing. In both cases, the consequence should be that the elderly get more vitamin B12 and not less folic acid which can have a protective effect in other areas.

This is the message – that is if you do not choose to believe that the new finding is a coincidence and that the truth is the exact opposite – which is actually also quite likely!

For the time being, however, Morris’ conclusion is simple: “We don’t know yet what is going on,” she says.

Up to every third elderly person may have demonstrable signs of mild vitamin B12 deficiency. If the results of the Chicago study are truthful, elderly persons possibly should not reduce their folic acid intake but rather focus on getting enough vitamin B12.

By: Vitality Council

References:
1. Morris MC et al. Dietary folate and vitamin B12 and cognitive decline among community-dwelling older persons. Arch Neurol 2005;62:641-5
2. Austin RC et al. Role of hyperhomocysteinemia in endothelial dysfunction and atherthrombotic disease. Cell Death and Differentiation 2004;11:S56-S64
3. Morris MS. Homocysteine and Alzheimers disease. Lancet Neurol 2003;2:425-8
4. Kado DM et al. Homocysteine versus the vitamins folate, B6, and B12 as predictors of cognitive function and decline in older high-functioning adults: Mac Arthur Studies of Successfull Aging. Am J Med 2005;118:161-7
5. Garcia A et al. Homocysteine and cognitive function in elderly people. CMAJ, Oct. 12, 2004; 171 (8).

archneur.ama-assn.org
www.nature.com/cdd/index.html
www.thelancet.com
www.sciencedirect.com
www.cmaj.ca
www.iom.dk

Supporting Evidence: B-vitamins Strengthen the Bones

Claus Hancke

March 18, 2005

A year ago a correlation between osteoporosis, folic acid and Vitamin B12 deficiency was discovered. It might have been a statistical coincidence, but a Japanese study discovered that the two vitamins reduced the risk of bone fracture by 80%.

Just a year ago, Dutch and American researchers demonstrated that at high homocysteine level – which is very common and most often a consequence of folic acid or vitamin B12 deficiency – the risk of breaking the hip doubles. It was only a statistical context, but was there also a causal link?

Can folic acid and/or vitamin B12 really reduce the risk of hip fracture, i.e. the most dangerous consequence of osteoporosis?

Few have considered this possibility before, but for now it seems to be a possibility. Japanese doctors have suspected this for at least five years. In 2000, they began a two-year treatment trial to investigate the matter.

The trial included 628 particularly vulnerable, elderly patients who received a solid dose of the two vitamins: 5 mg folic acid and 1.5 mg vitamin B12 per day. However, half received placebo (inactive tablets). The 628 were selected because they had had a stroke and were still more or less paralyzed on one side after a year. In this situation, the risk of breaking the hip is doubled, especially since the risk of falling is high.

Over the two years, it was recorded how often the participants in the two groups fell. They did so equally often. But the consequences were much milder in those who received the supplement. Only six of them suffered a hip fracture, while the same happened to 27 in the control group. The risk was therefore reduced by more than 80%. In the treated group, the blood level of homocysteine fell by a good 30%, while it increased by the same amount in those who received the inactive tablets.

B deficiency destroys connective tissue
There is a lot of talk about the argument that homocysteine is dangerous for bones. The new thing is that it is useful to lower it if it is high. Not because it will add more calcium to the bones. According to a Dutch study from 2004, it does not. On the other hand, there are good reasons to believe that the bone tissue you have will become stronger.

Biochemical experiments have shown that homocysteine attacks both elastic and other fibers in bone and connective tissue, so that the structure becomes looser, the interweaving of fibers less tight and the bones more rigid. Fibers of the same type are also found in the arteries, which can also be damaged, and chemically similar proteins participate in blood coagulation. Some believe that this explains the increased tendency for blood clots in the heart, etc., which is seen with elevated homocysteine.

The argument is supported by the fact that blood clots and weakened bones occur particularly early in people with the congenital disease “homocystinuria,” in which the blood level of homocysteine is 10 times higher than normal. The difference between them and others, it is said, is only the time at which the damage occurs.

If the Japanese study is confirmed, folic acid and vitamin B12 are simply the most effective protection against osteoporosis known! In any case, it is certainly not unwise to have your homocysteine level measured in your blood. It should not be much higher than 10 micromol/liter.

By: Vitality Council

References:
1. Sato Y, Honda Y, Iwamoto J, Kanoko T, Satoh K. JAMA. 2005 Mar 2;293(9):1082-8. Effect of folate and mecobalamin on hip fractures in patients with stroke: a randomized controlled trial.
2. Krumdieck CL et al. Mechanisms of homocysteine toxicity on connective tissues: Implications for the morbidity of aging. J Nutr. 2000;130:365S-368S.
3. Van Meurs Joyce B J et al. Homocysteine levels and the risk of osteoporotic fracture. N Engl J Med 2004;350:2033-41.
4. Mc Lean Robert R et al. Homocysteine as a predictive factor for hip fracture in older persons, N Engl J Med 2004;350:2042-9.

jama.ama-assn.org
content.nejm.org

Vitamin B12 helps against itching

Claus Hancke

September 6, 2004

Chronic itching can be effectively remedied with vitamin B12 – at least if the itching is due to childhood eczema, also called atopic eczema. The highly skin-soothing effect has been demonstrated by six German dermatologists in a quite simple experiment with 49 patients.

The itch-injured patients were each given two tubes of cream. One was a neutral moisturizer, while the other contained vitamin B12, otherwise available as tablets or as a solution for injection. In the following eight weeks, the patients lubricated the neutral cream on one side of the body and the B12 crem on the other side. After the eight weeks, both patients and doctors evaluated the result.

The effect was convincing. In approx. 60% of the cases the B12 vitamin cream, after both the doctor’s and the patient’s opinion, had resulted in a “good” or “very good” result. On the side of the body that had been treated with the moisturizer, the result was almost inevitably “moderate” or “bad”. Here too, doctors and patients agreed.

The B12 vitamin cream was exceptionally well tolerated and is quite harmless. The mode of action is thought to be that the vitamin in certain contexts is an effective antioxidant neutralizing NO (nitrogen oxide) in inflammated tissue.
It was known in advance that when you block the formation of NO in asthma medically, itching and rashes decreases. The new thing is that the same effect is achieved in this simple way by blocking NO when it is formed.

Itching is also a problem in many other skin diseases, just as many elderly suffer from chronic itching. If the vitamin works with other itchy conditions, it is unknown. An estimated 10% of elderly people in Britain suffer from vitamin B12 deficiency.

By: Vitality Council

 

Reference:
Stucker M, Pieck C, Stoerb C, Niedner R, Hartung J, Altmeyer P Topical vitamin B(12)-a new therapeutic approach in atopic dermatitis-evaluation of efficacy and tolerability in a randomized placebo-controlled multicentre clinical trial. Br J Dermatol. 2004;150(5):977-83.

www.blackwell-synergy.com/servlet/useragent

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Vitamin B12, Research references

Admin

January 1999

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