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Vitamin B12 deficiency can spell trouble

Ever wondered what vitamin B12 deficiency might mean? A severe vitamin B12 deficiency can lead to Multiple Sclerosis, deep depression, paranoia and delusions, memory loss, incontinence, loss of taste and smell and more.  What's even more unfortunate is that you may already have B12 deficiency without you knowing about it! Symptoms of this condition may only manifest after several years being influenced by your diet and your body’s ability to absorb B12.

What does vitamin B12 do?

The human body uses vitamin B12 to make red blood cells, nerves, DNA, as well as carry out different other functions. The average adult should get 2.4 micrograms a day. Like most vitamins, B12 is not made by our body. Instead, it must be gotten from your diet or supplements. 

So, here’s the problem: Some people don’t consume enough vitamin B12 to meet their needs, while others can’t absorb it, regardless of how much of it they consume. As a result, vitamin B12 deficiency is quite common, especially amongst the elderly. The American National Health and Nutrition Examination Survey estimated that 3.2% of adults over age 50 have a seriously low B12 level, and up to 20% may have a borderline deficiency. I couldn’t find any European data on this issue but I think it’s safe to assume that it is quite similar.

Reduced Absorption Due to Alcohol Consumption

Alcohol -- especially in large amounts -- irritates the mucosal lining of the stomach and intestines. When the stomach lining is irritated -- a condition called gastritis -- it produces less hydrochloric acid and may secrete less intrinsic factor too, both of which contribute to reduced B-12 absorption from food. Alcohol not only impairs nutrient absorption by damaging the lining of the gastrointestinal system, but it also prevents nutrients from being fully utilized in the body by altering their transport, storage and excretion. Furthermore, decreased hydrochloric acid production can stimulate the growth of intestinal bacteria that use B-12, which further reduces the amount available to your body.

Am I at risk?

There are many causes for vitamin B12 deficiency. Surprisingly, two of these are practices which are often undertaken by individuals in order to improve their health: a vegetarian or vegan diet and weight-loss surgery.

Plants don’t make vitamin B12. The only foods that contain it are meat, eggs, poultry, dairy products, and other animal derived foods. Strict vegetarians and vegans are often at a high risk for developing a B12 deficiency, especially if they don’t consume grains that have been fortified with B12 or take a B12 supplement. People who have stomach stapling or other form of weight-loss surgery such gastric bypass, sleeve etc., are also more likely to be low in vitamin B12 due to the fact that the operation interferes with the body’s ability to extract vitamin B12 from food.

Conditions that interfere with food absorption, such Coeliac or Crohn’s disease or alcoholism can cause B12 related issues. Similarly, the use of commonly prescribed heartburn drugs, which reduce acid production in the stomach (acid is needed to absorb vitamin B12) can cause trouble. The condition is more likely to occur in the elderly because of the cutback in stomach acid production that often happens with aging. 

Do I have a B12 deficiency?

Vitamin B12 deficiency can be slow to develop, triggering symptoms to appear gradually and intensify over time. It can also come on fairly quickly. Given the range of symptoms it can cause, the condition can be often overlooked or confused with other conditions. Symptoms may include:

  • (paraesthesia) - weird sensations, numbness, or tingling in the hands, legs, or feet difficulty with walking (staggering, balance problems)

  • anaemia

  • a swollen, inflamed tongue

  • mouth ulcers

  • yellowed skin (jaundice)

  • problems sleeping

  • difficulty thinking and reasoning (cognitive difficulties), or memory loss

  • paranoia or hallucinations

  • muscle weakness

  • fatigue

  • disturbed vision

  • irritability

  • depression

  • mood swings


Whilst a competent healthcare practitioner may be able to suspect a vitamin B12 deficiency during interview and physical examination, a blood test is required to confirm the condition.

However, a particular drawback of testing vitamin B12 levels is that the current widely-used blood test only measures the total amount of vitamin B12 in your blood.

This means it measures forms of vitamin B12 that are "active" and can be used by your body, as well as the "inactive" forms, which can't. If a significant amount of the vitamin B12 in your blood is "inactive", a blood test may show that you have normal B12 levels, even though your body can't use much of it.

There are some types of blood test that may help determine if the vitamin B12 in your blood can be used by your body, but these aren't yet widely available.

One of these test is for Homocysteine which is normally elevated when B12 is deficient. Vegans and vegetarians should read this article.  And if you’re vegan or vegetarian and you’re also pregnant or trying to become pregnant, please read this.


Early detection and treatment is essential. If left untreated, the deficiency can lead to severe neurologic problems and blood diseases.

What your sleeping difficulties may be trying to tell you

If you have a sleeping problem, I recommend taking vitamin B12 during the day. I believe it can help you because B12 plays a vital role in melatonin production. Melatonin has been called "the sleep hormone" because it is responsible enabling get a good night's sleep.  

As you age, it becomes increasingly more difficult to get a good night's sleep because your body becomes less efficient at making this hormone. And that's why it's a good idea to take B12 to help you sleep like a baby each night.

B(e) proactive

It’s a good idea to have your B12 level checked if you:

  • are over 50 years’ old

  • consume large quantities of alcohol

  • take a proton-pump inhibitor (such as Nexium or Prevacid) or H2 blocker (such as Pepcid or Zantac)

  • take metformin (a diabetes drug)

  • are a strict vegetarian or vegan

  • have had weight-loss surgery or have a condition that interferes with the absorption of food


A serious vitamin B12 deficiency may be modified in one of two manners:

  • weekly shots of vitamin B12; or

  • daily high-dose B12 tablets.


A mild B12 deficiency can be corrected with a good quality multivitamin such as Multithera.

In many cases, a vitamin B12 deficiency can be prevented or avoided. If you are a strict vegetarian or vegan, it’s important to eat breads, cereals, or other grains that have been fortified with vitamin B12, or take a daily supplement. A standard multivitamin delivers 6 micrograms whereas Multithera contains 200 micrograms, more than enough to combat B12 deficiency.

If you are over age 50, the Institute of Medicine recommends that you get extra B12 from a supplement, since you may not be able to absorb enough of the vitamin through foods. A standard multivitamin should be enough but a potent multivitamin such as Multithera is superior.

You don't have to worry about a vitamin B12 overdose because it's water soluble, so "your body takes what it needs and flushes out the rest.

Not a cure

The Internet is full of articles praising the use of vitamin B12 to prevent Alzheimer’s disease, cardiovascular disease, and other chronic conditions or reverse infertility, fatigue, eczema, and a long list of other condition. Most of these resources are based on poor or faulty evidence.

As an example, Alzheimer’s disease related, there is a relationship between low vitamin B12 levels and cognitive decline, clinical studies—including those involving people with Alzheimer’s disease—have not shown improvement in cognitive function, even with doses of the vitamin as high as 1000 micrograms.

The bottom line is that it’s best to get enough vitamin B12 to prevent a deficiency, and not rely on it as a remedy for what makes you ill.

Another thing to keep in mind is that you can eat plenty of meat, poultry, lamb's liver, brewer's yeast, clams, eggs, herring, mackerel, kidneys, milk, dairy products, or seafood -- and still have low levels of B12, because your body is unable to absorb it from your gut.  This is due to the fact that B12 needs the help of a protein called Intrinsic Factor in order to be absorbed. Intrinsic Factor is made by the lining of the stomach and therefore people with less-than-optimal gastrointestinal health often need to supplement with B12

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