http://veganoutreach.org/health/b12letter.html
An Open Letter from Health Professionals and Vegan Organizations
What Every Vegan Should Know about Vitamin B12
Very low B12 intakes can cause anemia and nervous system damage.
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. Vitamin B12, whether in supplements,
fortified foods, or animal products, comes from micro-organisms.
Most vegans consume enough B12 to avoid anaemia and nervous system
damage, but many do not get enough to minimize potential risk of heart
disease or pregnancy complications.
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 (mcg or mg) of B12 a day or
take one B12 supplement daily providing at least 10 micrograms or
take a weekly B12 supplement providing at least 2000 micrograms.
If relying on fortified foods, check the labels carefully to make sure
you are getting enough B12. For example, if a fortified plant milk
contains 1 microgram of B12 per serving then consuming three servings
a day will provide adequate vitamin B12. Others may find the use of
B12 supplements more convenient and economical.
The less frequently you obtain B12 the more B12 you need to take, as
B12 is best absorbed in small amounts. The recommendations above take
full account of this. There is no harm in exceeding the recommended
amounts or combining more than one option.
Good information supports vegan health, pass it around.
If you don’t read another word about B12, you already know all you
need to know. If you want to know more, read on.
This information sheet was prepared by Stephen Walsh, a UK Vegan
Society trustee, and other members of the International Vegetarian
Union science group (IVU-SCI), in October 2001.
This information may be freely reproduced but only in its entirety
(list of endorsers may be omitted). Endorsers include:
EVA – Ethisch Vegetarisch Alternatief, Belgium
Farm Animal Reform Movement (FARM)
People for the Ethical Treatment of Animals
Vegan Action, US
Vegan Outreach, US
The Vegan Society, (UK)
Paul Appleby, medical statistician, UK
Dr Luciana Baroni, MD, Neurologist-Geriatrician, President of Società
Scientifica di Nutrizione Vegetariana, Italy
Amanda Benham, RD, Australia
Dr Glynis Dallas-Chapman, MB, BS, UK
Brenda Davis, RD, Co-author of Becoming Vegan and former Chair of the
Vegetarian Nutrition Dietetic Practice Group of the American Dietetic
Association
Dr William Harris, MD, USA
Alex Hershaft, PhD, President, FARM
Stephen R. Kaufman, MD, USA
Dr Gill Langley, MA PhD MIBiol, author of Vegan Nutrition, UK
Vesanto Melina, MS, RD, Co-author of Becoming Vegan,
www.nutrispeak.com
Virginia Messina, MPH, RD, Co-author of the Dietitian's Guide to
Vegetarian Diets, vegrd.com
Jack Norris, RD, Vegan Outreach director and author of Staying a
Healthy Vegan and a B12 Review
Dr John Wedderburn, MB, ChB, Founder of the Hong Kong Vegan Society
Vitamin B12 and Vegan Diets
Lessons from history
B12 is an exceptional vitamin. It is required in smaller amounts than
any other known vitamin. Ten micrograms of B12 spread over a day
appears to supply as much as the body can use. In the absence of any
apparent dietary supply, deficiency symptoms usually take five years
or more to develop in adults, though some people experience problems
within a year. A very small number of individuals with no obvious
reliable source appear to avoid clinical deficiency symptoms for
twenty years or more. B12 is the only vitamin that is not recognized
as being reliably supplied from a varied wholefood, plant-based diet
with plenty of fruit and vegetables, together with exposure to sun.
Many herbivorous mammals, including cattle and sheep, absorb B12
produced by bacteria in their own digestive system. B12 is found to
some extent in soil and plants. These observations have led some
vegans to suggest that B12 was an issue requiring no special
attention, or even an elaborate hoax. Others have proposed specific
foods, including spirulina, nori, tempeh, and barley grass, as
suitable non-animal sources of B12. Such claims have not stood the
test of time.
In over 60 years of vegan experimentation only B12 fortified foods and
B12 supplements have proven themselves as reliable sources of B12,
capable of supporting optimal health. It is very important that all
vegans ensure they have an adequate intake of B12, from fortified
foods or supplements. This will benefit our health and help to attract
others to veganism through our example.
Getting an adequate amount of B12
National recommendations for B12 intakes vary significantly from
country to country. The US recommended intake is 2.4 mcgs a day for
ordinary adults rising to 2.8 mcgs for nursing mothers. The German
recommendation is 3 mcgs a day. Recommended intakes are usually based
on 50% absorption, as this is typical for small amounts from foods. To
meet the US and German recommendations you need to obtain sufficient
B12 to absorb 1.5 mcgs per day on average. This amount should be
sufficient to avoid even the initial signs of inadequate B12 intake,
such as slightly elevated homocysteine and MMA levels, in most people.
Even slightly elevated homocysteine is associated with increased risk
of many health problems including heart disease in adults,
preeclampsia during pregnancy and neural tube defects in babies.
Achieving an adequate B12 intake is easy and there are several methods
to suit individual preferences. Absorption of B12 varies from about
50%, if about 1 mcg or less is consumed, to about 0.5% for doses of
1000 mcgs (1 mg) or above. So the less frequently you consume B12, the
higher the total amount needs to be to give the desired absorbed
amount.
Frequent use of foods fortified with B12 so that about one microgram
of B12 is consumed three times a day with a few hours in between will
provide an adequate amount. Availability of fortified foods varies
from country to country and amounts of B12 vary from brand to brand,
so ensuring an adequate B12 supply from fortified foods requires some
label reading and thought to work out an adequate pattern to suit
individual tastes and local products.
Taking a B12 supplement containing ten mcgs or more daily provides a
similar absorbed amount to consuming one mcg on three occasions
through the day. This may be the most economical method as a single
high potency tablet can be consumed bit by bit. 2000 mcgs of B12
consumed once a week would also provide an adequate intake. Any B12
supplement tablet should be chewed or allowed to dissolve in the mouth
to enhance absorption. Tablets should be kept in an opaque container.
As with any supplement it is prudent not to take more than is required
for maximum benefit, so intakes above 5000 mcg per week should be
avoided despite lack of evidence for toxicity from higher amounts.
All three options above should meet the needs of the vast majority of
people with normal B12 metabolism. Individuals with impaired B12
absorption may find that the third method, 2000 mcg once a week, works
best as it does not rely on normal intrinsic factor in the gut. There
are other, very rare, metabolic defects that require completely
different approaches to meeting B12 requirements. If you have any
reason to suspect a serious health problem seek medical advice
promptly.
Symptoms of B12 deficiency
Clinical deficiency can cause anaemia or nervous system damage. Most
vegans consume enough B12 to avoid clinical deficiency. Two subgroups
of vegans are at particular risk of B12 deficiency: long-term vegans
who avoid common fortified foods (such as raw food vegans or
macrobiotic vegans) and breastfed infants of vegan mothers whose own
intake of B12 is low.
In adults typical deficiency symptoms include loss of energy,
tingling, numbness, reduced sensitivity to pain or pressure, blurred
vision, abnormal gait, sore tongue, poor memory, confusion,
hallucinations and personality changes. Often these symptoms develop
gradually over several months to a year before being recognized as
being due to B12 deficiency and they are usually reversible on
administration of B12. There is however no entirely consistent and
reliable set of symptoms and there are cases of permanent damage in
adults from B12 deficiency. If you suspect a problem then get a
skilled diagnosis from a medical practitioner as each of these
symptoms can also be caused by problems other than B12 deficiency.
Infants typically show more rapid onset of symptoms than adults. B12
deficiency may lead to loss of energy and appetite and failure to
thrive. If not promptly corrected this can progress to coma or death.
Again there is no entirely consistent pattern of symptoms. Infants are
more vulnerable to permanent damage than adults. Some make a full
recovery, but others show retarded development.
The risk to these groups alone is reason enough to call on all vegans
to give a consistent message as to the importance of B12 and to set a
positive example. Every case of B12 deficiency in a vegan infant or an
ill informed adult is a tragedy and brings veganism into disrepute.
The homocysteine connection
This is not however the end of the story. Most vegans show adequate
B12 levels to make clinical deficiency unlikely but nonetheless show
restricted activity of B12 related enzymes, leading to elevated
homocysteine levels. Strong evidence has been gathered over the past
decade that even slightly elevated homocysteine levels increase risk
of heart disease and stroke and pregnancy complications. Homocysteine
levels are also affected by other nutrients, most notably folate.
General recommendations for increased intakes of folate are aimed at
reducing levels of homocysteine and avoiding these risks. Vegan
intakes of folate are generally good, particularly if plenty of green
vegetables are eaten. However, repeated observations of elevated
homocysteine in vegans, and to a lesser extent in other vegetarians,
show conclusively that B12 intake needs to be adequate as well to
avoid unnecessary risk.
Testing B12 status
A blood B12 level measurement is a very unreliable test for vegans,
particularly for vegans using any form of algae. Algae and some other
plant foods contain B12-analogues (false B12) that can imitate true
B12 in blood tests while actually interfering with B12 metabolism.
Blood counts are also unreliable as high folate intakes suppress the
anaemia symptoms of B12 deficiency that can be detected by blood
counts. Blood homocysteine testing is more reliable, with levels less
than 10 mmol/litre being desirable. The most specific test for B12
status is methylmalonic acid (MMA) testing. If this is in the normal
range in blood (<370 nmol/L) or urine (less than 4 mg /mg creatinine)
then your body has enough B12. Many doctors still rely on blood B12
levels and blood counts. These are not adequate, especially in vegans.
Is there a vegan alternative to B12-fortified foods and supplements?
If for any reason you choose not to use fortified foods or supplements
you should recognize that you are carrying out a dangerous experiment
- one that many have tried before with consistently low levels of
success. If you are an adult who is neither breast-feeding an infant,
pregnant nor seeking to become pregnant, and wish to test a potential
B12 source that has not already been shown to be inadequate, then this
can be a reasonable course of action with appropriate precautions. For
your own protection, you should arrange to have your B12 status
checked annually. If homocysteine or MMA is even modestly elevated
then you are endangering your health if you persist.
If you are breast feeding an infant, pregnant or seeking to become
pregnant or are an adult contemplating carrying out such an experiment
on a child, then don’t take the risk. It is simply unjustifiable.
Claimed sources of B12 that have been shown through direct studies of
vegans to be inadequate include human gut bacteria, spirulina, dried
nori, barley grass and most other seaweeds. Several studies of raw
food vegans have shown that raw food offers no special protection.
Reports that B12 has been measured in a food are not enough to qualify
that food as a reliable B12 source. It is difficult to distinguish
true B12 from analogues that can disrupt B12 metabolism. Even if true
B12 is present in a food, it may be rendered ineffective if analogues
are present in comparable amounts to the true B12. There is only one
reliable test for a B12 source – does it consistently prevent and
correct deficiency? Anyone proposing a particular food as a B12 source
should be challenged to present such evidence.
A natural, healthy and compassionate diet
To be truly healthful, a diet must be best not just for individuals in
isolation but must allow all six billion people to thrive and achieve
a sustainable coexistence with the many other species that form the
“living earth”. From this standpoint the natural adaptation for most
(possibly all) humans in the modern world is a vegan diet. There is
nothing natural about the abomination of modern factory farming and
its attempt to reduce living, feeling beings to machines. In choosing
to use fortified foods or B12 supplements, vegans are taking their B12
from the same source as every other animal on the planet –
micro-organisms – without causing suffering to any sentient being or
causing environmental damage.
Vegans using adequate amounts of fortified foods or B12 supplements
are much less likely to suffer from B12 deficiency than the typical
meat eater. The Institute of Medicine, in setting the US recommended
intakes for B12 makes this very clear. “Because 10 to 30 percent of
older people may be unable to absorb naturally occurring vitamin B12,
it is advisable for those older than 50 years to meet their RDA mainly
by consuming foods fortified with vitamin B12 or a vitamin
B12-containing supplement.” Vegans should take this advice about 50
years younger, to the benefit of both themselves and the animals. B12
need never be a problem for well-informed vegans.
Good information supports vegan health, pass it around.
Further information:
Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6,
Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline, National
Academy Press, 1998 ISBN 0-309-06554-2
Vitamin B12: Are you getting it?, by Jack Norris, RD
Homocysteine in health and disease, ed. Ralph Carmel and Donald W.
Jacobsen, Cambridge University Press, 2001, ISBN 0-521-65319-3
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Hansom <0>++<0>
Avoid the rush at the last judgement. Be converted now instead!
PRAYER FOR A NATION
When Pastor Joe Wright, of Central Christian Church, was asked
to open the new session of the Kansas Senate, everyone was expecting
the usual politically correct generalities.
But what they heard instead was this:
Heavenly Father, we come before You today to ask Your forgiveness
and seek your direction and guidance.
We know Your Word says,
‘Woe on those who call evil good,’ but that’s exactly what we have done.
We have lost our spiritual equilibrium and inverted our values.
We confess that:
We have ridiculed the absolute truth of Your Word and called it pluralism;
We have, worshipped other gods and called it multiculturalism;
We have endorsed perversion and called it an alternative lifestyle;
We have exploited the poor and called it the lottery;
We have neglected the needy and called it self-preservation;
We have killed our unborn and called it choice;
We have neglected to discipline our children and called it building self-esteem;
We have abused power and called it political savvy;
We have coveted our neighbour’s possessions and called it ambition;
We have polluted the air with profanity and pornography and called it freedom of expression;
We have ridiculed the time-honoured values of our forefathers and called it enlightenment.
Search us, 0 God, and know our hearts today; try us and see if there be some wicked way in us;
cleanse us from every sin and set us free. Guide and bless these men and women who have
been sent here by the people of Kansas, and who have been ordained by You, to govern this great state.
Grant them Your wisdom to rule and may their decisions direct us to the centre of Your will. I ask it in the name of Your Son, the Living Saviour, Jesus Christ. Amen.”
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