B12 Deficiency Patient Support Group A forgotten illness - Getting your life back

 Please note: a variety of sources of evidence is given here. Some are from peer-reviewed sources (medical journals) and some are more popular. The scientific community gives little credibility to non peer-reviewed sources; however they are often easier to read.
DNA and genes
Each and every working cell in the human/every living thing body contains a nucleus and the nucleus basically consists of DNA and its protective proteins. The DNA contains the blueprints to every protein the body makes, and the proteins then make everything else happen including consuming food, growing, moving, thinking, fighting off disease, hormones etc).
B12 seems to mainly affect which genes are read when – but this in turn affects

• how DNA is copied (which could affect whether mutations get passed on to daughter cells and the next generation of children)(Piyathilake, Johanning et al. 2000; Elias, Peeters et al. 2005),
• when a particular gene switches on and off (many long-term conditions such as obesity, diabetes, heart disease are affected by whether a gene is left switched on too long. Cancer is a particularly clear example of a gene not being switched off in time)(Piyathilake, Johanning et al. 2000; Elias, Peeters et al. 2005)

Mood chemicals
A low mood or depression chemical, homocysteine, are converted to chemicals important to the body by a process involving B12. This is so sensitive that high levels of homocysteine have been used as an indicator to decide if someone has B12 deficiency, though other things can cause high homocysteine so this may not be a particularly specific test for B12 deficiency (Nilsson, Gustafson et al. 1994).
The result of low B12 (or B12 lower than the body needs) is that this low mood chemical accumulate and the sufferer feels a non-specific depression or sadness, which combined with many of the other symptoms such as tiredness can lead to a spiral downwards in mood.
Excess of homocysteine may also lead to dementia (loss of cognitive function which means the inability to think or remember)(Diaz-Arrastia 1998; Diaz-Arrastia 2000; Hultberg, Isaksson et al. 2001). B12 deficient patients notice this because dementia or poor memory and thinking may come and go (similar to the relapsing/ remitting nature of multiple-sclerosis). The problems may be solved by B12 in isolation, or may require a combination – for example B12 and folic acid work together on many pathways including the homocysteine pathway (Nilsson, Gustafson et al. 2001).
Energy production
Once foodstuffs get into the cell they are transported to organelles (literally “little organs”) called mitochondria, which produce energy. Basically they take sugars, fats, any carbohydrates they can lay their bits on, and turn them into energy (not sparks of electricity, the body’s universal fuel ATP – which you can’t buy in shops because it is too powerful and unstable).
The mitochondria have different transport proteins to get the B12 in(Coelho, Suormala et al. 2008), and then B12 is absolutely vital for the production of energy in the mitochondria. People suffering from B12 deficiency often find they lack energy, can be extremely tired and at the same time not have the energy to get to sleep at night(Coelho, Suormala et al. 2008; Miousse, Watkins et al. 2009; Myhill, Booth et al. 2009).
If left untreated, this results in the wasting disease reported by Combe (1824), Addison (1859), Russell (1900) and many others reported in (Chanarin 1969) in the 19th C and throughout the 20th C as ME, Post Viral Chronic Fatigue Syndrome, Fibromyalgia
Lipid processing in particular Cell membrane manufacture and maintenance
Cell membranes are vital for all sorts of things. Examples include nerve cell conduction (next), endocrine system (all of the hormones), digestive function, immune function
Nerve Maintenance – the nerve signal is transmitted along an axon (the wire) surrounded by a myelin sheath (the insulation). The myelin sheath is essentially a special cell which wraps itself around the axon many times forming many layers of cell membrane – and as the cell membrane is made up of lipids this is an insulating layer allowing the signal to travel down the nerve.
The myelin needs B12 to build itself and repair (most cells go through a natural cycle of break down and repair, and if the repair doesn’t work then the natural cycle continues to break down the sheath). Without the myelin sheath, the nerve can’t transmit a signal. Eventually the nerve gives up and dies. (Scalabrino 2009)(Scalabrino, Veber et al. 2007)
People suffering from B12 deficiency experience this damage in a number of ways – for example shooting pains, pins and needles, numbness, paralysis and/or loss of power or grip; if left untreated it can result in Multiple Sclerosis(Scalabrino 2005; van Rensburg, Kotze et al. 2006; Ascherio and Munger 2007; Solomon 2007; Kocer, Engur et al. 2009; Scalabrino 2009; Stewart 2009; Turner and Talbot 2009). In particular, the nerves in hands and feet which are unmyelinated, for detecting temperature and vibration, may be particularly sensitive to B12 deficiency and may lead to the numbness and pins and needles which people report as early symptoms (Smith, Ali et al. 1991)
Demyelination can also show up as ‘the fogs’, a feeling of confusion and not being able to think. Of course there are bundles of nerves to the eye, the tongue, the throat, so a shortage of B12 can cause blindness (especially in one eye), inability to swallow and so on (see http://b12d.org/content/B12-signs-symptoms-assessment-form).
One characteristic of B12 deficiency is a loss of balance – there’s a particular sideways walk called ataxia which is characteristic of B12 deficiency.(McBride 2000)
Scalabrino in Italy showed that when a mouse is deprived of B12, it first develops symptoms like Multiple Sclerosis (MS), and eventually develops the characteristic plaques that define MS (Scalabrino 2005). What more proof do you need of a connection?
Immune system – also uses the cell membrane; special cells can detect ‘foreign’ and ‘self’ proteins in the body or on the surface of organisms like bacteria. Sometimes it breaks down and doesn’t recognise ‘self’; antibodies (the signals that call the phagocytes or cleanup cells to an infection) are produced and the immune system will start to destroy your body from the inside – a condition called an Autoimmune disease.
Autoimmune diseases can attack any part of the body (they usually attack a single type of cell). For example, one form of the condition produces antibodies to cells in the stomach, the parietal cells (Qureshi, Rosenblatt et al. 1994; Oh and Brown 2003).
Correspondence on the WD thread suggests that established autoimmune conditions seldom exist alone; Hashimoto's Thyroiditis seems to be a particularly common companion to PA. It's not an area that I have personal experience of, so I'm no expert. One writer, though (unfortunately no longer posting), was particularly good on the subject; he said that there's actually a kind of autoimmune quintet. If you develop one, then wait (or live) long enough, you'll eventually stand a chance of collecting the whole set - PA, Hashimoto's, Alopecia, Vitiligo, Coeliac.
He seemed to know what he was talking about, and he had the lot. He had gone looking for coeliac disease when he had realised that he had the other four, and had been persistent enough - via his GP and referrals - to have its presence diagnosed. I could find nothing on the Net connecting all five. There is, however, plenty of stuff connecting any two or three. (these last two paragraphs from Kevin Byrne) 
These will either show up as Parietal Cell antibodies or Intrinsic Factor (IF) antibodies, though they both have the same effect – it means the body starts to attack cells which produce all of the digestive chemicals in the stomach including hydrochloric acid, the proteases and intrinsic factor. Without intrinsic factor you can’t absorb B12, which means the autoimmune disease is likely to get worse. Your stomach may atrophy, which essentially means that it has died and doesn’t work.
There are a number of other autoimmune diseases; they can affect nerve cells, organs and so on. We believe that if your B12 is low then you could develop an autoimmune disease, though which one could depend on a variety of other factors.
With a mal-functioning immune system you will probably be prone to all sorts of other things like colds, cracked skin, fungal infections, infections and sores, etc.
Endocrine system – hormones control all the things that you don’t stop to think about: how you feel from moment to moment (angry, alert, relaxed, happy, ready for action); how you grow, the menstrual cycle, how you age, everything that isn’t controlled by nerves. 
The endocrine system also relies on cell membranes and special glands in the membrane to secrete the hormones. Lack of B12 can upset the cell membranes and the special glands, meaning hormones start to go wrong, in particular the thyroid hormones (Nilsson-Ehle 1998).
Mostly this shows up when a woman has irregular periods and can’t conceive (Menachem, Cohen et al. 1994; Elias, van Noord et al. 2005). But it can also show when you’re prone to disease, weepy or irritable all of the time (snappy), tired, depressed. But for long-term deficiency, you might see problems with growing and puberty. The sad thing is that if B12 deficiency goes on this long, the patient is probably very near death for other reasons.

Documents Relied On
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