Vitamin B12 – Who needs it?

I get asked a lot about vitamin B12. Is vitamin b12 deficiency common? Who needs b12 supplements? Which form b12 vitamin supplement is the best choice? Here are the answers.

How common is B12 vitamin deficiency?
Vitamin B12 deficiency is more common than you think, especially in the elderly population. For example one study made in Europe noted that 6,1% of over over 65 years old people had substantial vitamin B12 deficiency and 32% were on brink of deficiency.1

Of course, you may think that this is not the case in the United States, here things are better. Unfortunately, when you look at studies you notice that things are not much better.

For example: Framingham Offspring study 2 noted: up to 39% of participants vitamin B12 level was less than 258 pmol/L (less than ideal). And in 17% of participants levels were only about 185 pmol/L (near the deficient). But the real shock was that 9% of people b12 vitamin levels were less that 148pmol/L which is a clear deficiency of vitamin B12, according to latest science.3

“In large surveys in the United States and the United Kingdom, ≈6% of those aged ≥60 y are vitamin B-12 deficient (plasma vitamin B-12 < 148 pmol/L), with the prevalence of deficiency increasing with age. Closer to 20% have marginal status (plasma vitamin B-12: 148–221 pmol/L) in later life. In developing countries, deficiency is much more common, starting in early life and persisting across the life span. Inadequate intake, due to low consumption of animal-source foods, is the main cause of low serum vitamin B-12 in younger adults and likely the main cause in poor populations worldwide; in most studies, serum vitamin B-12 concentration is correlated with intake of this vitamin.” – Source

Vitamin B12 overview video

Why vitamin B12 deficiency is common?

There are two ways to get vitamin B12 deficiency: you don’t get it enough from a diet, or your vitamin B12 absorption is impaired.

The older you are the more likely you will have defects that cause vitamin B12 absorption problems.

The most common reason for a vitamin B12 deficiency is malabsorption.

As we age, our bodies stomach acid production begins to decline, which reduces hydrochloric acid in the stomach. Hydrochloric acid excretes vitamin B12 from food and if its production is reduced, it also reduces vitamin B12 absorption.

In addition, the use of various medication and heartburn drugs results in decreased production of gastric acid, which impairs the absorption of vitamin b12.

Other reasons which may cause vitamin B12 deficiency:

Regime reasons: vegetarian diet, excessive use of alcohol, drink too much a coffee, don’t eat foods which have vitamin b12

Stomach and intestinal cause: pernicious anemia, Helicobacter pylori infection, Tapeworm, Crohn’s disease, Atrophic gastritis.

Lack of folic acid: celiac disease, alcoholism, pregnancy (increased demand), Medicines.

What you should eat to get enough vitamin B12?
High-quality meat, lamb, liver, poultry, clams, eggs, herring, mackerel, kidneys, dairy products, and fish.

If your diet has enough the above-mentioned foods, you may not need vitamin B12 supplements prior to retirement age.

But we must remember even if your diet is perfect, you can still have vitamin B12 deficiency because of problems with the absorption.

If you are a vegan…
Many people are avoiding red meat these days for a number of rational reasons. However, they have a higher risk of developing vitamin B12 deficiency, because the plant-derived diet has virtually none vitamin B12. That’s the reason vegans should take vitamin B12 supplement.

Symptoms that may indicate vitamin B12 deficiency

Most surprising b12 vitamin deficiency symptom is sleeping problems. Vitamin B12 is a vital part of the production of melatonin.4 Without melatonin, you will not get a good sleep and without vitamin B12 you might have problems producing melatonin. If you have trouble sleeping, you may notice a dramatic difference after taking vitamin B12 supplement.

Other symptoms that may be indicative of vitamin b12 deficiency
– Fatigue
– Depression
– Poor or worsening of vision
– loss of appetite
– Unexpected weight loss
– Constipation or bloating
– Mood swings
– Lack of motivation “reluctance”
– The tendency to nervousness
– Digestive Problems
– Balance Problems
– Muscular debility
– Itching of the extremities
– Memory problems
– Gray hairs
– Liver or heart problems

Generally, it is believed that vitamin B12 deficiency is behind the current proliferation of memory disorders.5 However, more recent studies with a B-vitamin supplements have not show significant benefits in elderly people.6–8

Video how vitamin b12 deficiency affects brain?

Blood tests for vitamin B12 levels

B12 vitamin deficiency is almost impossible to detect without a blood test. If you have the above problems you should consider vitamin B12 blood test.

Here is the blood test’s that give can give good information about your vitamin B12 levels.

Serum vitamin B12 Levels
As the name suggests, this blood test tells your blood vitamin b12 content. However, you should be aware that this test result does not tell you more than your blood vitamin B12 levels. Even though this value would be within the reference range, you can still suffer from vitamin B12 deficiency.

The normal reference range depends on the country you are living, but generally, it’s considered to be 300 – 1000 pg/mL. Usually, you have vitamin b12 deficiency if your is serum vitamin B12 level is lower than 300 pg/mL and severe deficiency if your levels are under 200 pg/mL.

In Japan normal reference range is 500–1,300 pg/mL.9

Nowadays, this blood test is not actually used for examining vitamin B12 deficiency, because there are more accurate tests for vitamin B12. But if you want just some information about your B12 vitamin levels, this test is about five times cheaper than the measurement of the active vitamin B12.

Active Vitamin B12 Holotranscobalamin
This blood test tells the amount of active vitamin B12 in your blood.

The determination of active vitamin B12 (S-B12-TC2) is better than the determination of the total vitamin B12 content because it does not measure inactive haptocorrin bound vitamin. When the active vitamin B12 content is below 20 pmol/l, the result strongly suggests a deficiency of vitamin B12.

However, in the limit range of 20-50 pmol/l vitamin B12 deficiency is possible. Further investigations of the determinations of homocysteine or more specific Methylmalonic acid test should be considered.

Homocysteine from plasma
Homocysteine levels rise in folic acid, vitamin B12, or vitamin B6 deficiency. Plasma homocysteine levels are affected by both genetic and nutritional factors.

Normal range hovers around 4-10 μmol/L.

Methylmalonic acid (MMA)
When you have vitamin B12 deficiency, your Methylmalonic acid level start to rise. Taking MMA test can tell if you have early vitamin B12 deficiency. It’s used mainly when your other b12 levels are little below the normal reference range. sells methylmalonic acid home test kits, but they are kinda expensive.

Vitamin b12 benefits

Vitamin b12 is commonly known about its effects for energy levels and vitality. In addition, it is required digestion and fat metabolism. It is also a critical component of healthy skin, hair, nails and helps their regeneration.

Vitamin B12 is also important for the brain, and it is often said to help increase mental capacity and to remain stable as we learned in natural nootropics article. Vitamin B12 is also used in the prevention of anxiety and depression, as in studies many depressed people have been found to have low B-12 and folate levels.10–12

Also one Finnish study showed that antidepressants perform better with people who have higher levels of vitamin B12.

Vitamin B12 side effects and overdose

B12 is a water soluble vitamin and its absorption is always small, in addition to the body is able to filter off the excess with urine. In addition, the more you take vitamin B-12 the absorption is reduced automatically. So vitamin b12 overdose is almost impossible unless you don’t constantly overdose it.

For this reason, in many a number of b12 supplements can have single dose can be up to 60.000% of recommended daily allowance. But, of course, it is not worth to begin to take overdoses in vain, because overdoses can cause the same symptoms as a deficiency.

A long-term overdose of vitamin B12 may cause the following symptoms:
– Numbness or tingling in the feet or hands.
– Nervousness, Panic Attacks.
– Sleeping problems.
– Rashes.
– Mild diarrhea.
– Heartburn.

I would not be too much concerned about vitamin b12 overdose because it is very rare. But once in a while, you should take breaks B12 dietary supplements, in particular with sprays in which the daily dose can be 100x times the intake recommendations.

Of course, you can always fix the original problem, in your diet. Try to eat more foods containing vitamin B12. It’s impossible to get vitamin b12 overdose from foods.

What kind of vitamin B12 dietary supplement you should choose?

There has been a lot question about vitamin B12 supplements – so here is the quick guide for choosing b12 supplements.

The market generally consists of a synthetic and natural form of vitamin b12 forms: such as hydroxocobalamin, cyanocobalamin, adenosylcobalamin, and methylcobalamin.

Not recommend forms:
The most common vitamin b12 supplements are in the form of cyanocobalamin. The problem with this type of B12 is that the body needs to manually convert it methylcobalamin and 5’deoxyadenosylcobalamin before it affects. Worst choice in general.

Bioavailable form:
In nature, vitamin B12 is occurring in the form of methylcobalamin and adenosylcobalamin. In blood vitamin B12 is on methylcobalamin and 5’deoxyadenosylcobalamin. Methylcobalamin is bioactive, which means that the body does not need to produce any chemical reaction before it starts to affect.

So generally, you should choose to use spray or tablet which consist of methylcobalamin.

Where to get vitamin B12 supplements?

b12 vitamin supplementsAbove all, I recommend putting your diet better shape in order to get enough vitamin B12. However, for vegans, that is not possible. Here is recommended vitamin b12 supplements.

When selecting your vitamin B12 supplement, it’s wise to pay attention to the form of vitamin b12. For most people best choice for B12 vitamin is the natural methylcobalamin form.

I personally use this methylcobalamin spray (perfectly suitable for vegans).

One bottle is enough to last at least 6 months, even if you use it daily. It has a mild sweet taste, even there is no sweetener.

175 doses: 500mcg per dose. I recommend taking a maximum of 500mcg (20.000% of recommended daily allowance) per day. Of course, you can take more if you know that you have vitamin B12 deficiency, or you have a vitamin B12 malabsorption, or you do not eat foods containing vitamin B12.

One methylcobalamin spray bottle at cost around 12 dollars (Special discount for readers: You get 5% discount from if you use links in this article.)

I also use this B-complex which provides all the B vitamins in a bioactive form. 1 capsule a day is enough to ensure optimal vitamin B intake, at least if the diet is in a relatively good condition. When you take this, you do not need to take vitamin B12 separately.


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