B12 (348) with symptoms? Could it be? - Pernicious Anaemi...

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B12 (348) with symptoms? Could it be?

bkerch55 profile image


I have been battling ongoing symptoms for the last 7 months. Brain fog, disorientation, daily tension headaches, muscle weakness, Hot flashes, diarrhea and fatigue to name a few. I have dont MRI's, Cat scans , ultrasounds and even a colonoscopy. All my blood work has always come back normal. Just the other day my doctor decides to check my B12, Ferritin, Folate. Below were my numbers. Could it really have been B12 the whole time? I read that the 300 range was normal. My doc gave me a B12 shot right away and has me on 1000 a day. I am 27 years old.

B12 - 348

Ferritin- 174

Folate -18.3

10 Replies
Gambit62 profile image

There are three problems with serum B12 - a) its only accurate to 20% and b) it only tells you what is going on in your blood - not what is going on in your cells and c) Serum B12 also has a huge range - ie a lot of variation in where people are okay - but an individual tends to have a range that is right for them - so it is quite difficult to tell from a single measurement if an individual is actually okay - and you do need to look at symptoms quite carefully.

It may be that you had an earlier B12 test that showed a higher level - a significant drop is indicative of an absorption problem.

B12 deficiency tends to creep up on you very slowly - years or even decades so sometimes you don't notice that you have symptoms until it all starts to snowball. You can find symptoms here


Suggest you keep a diary of symptoms and see how they change with time - some people can manage with high dose oral supplements but there are some for whom it just doesn't work and there is a huge variation in how frequently people need injections.

It would be helpful to know what country you are in as treatment protocols can vary considerably.

bkerch55 profile image
bkerch55 in reply to Gambit62

I am actually in the United States. I guess my question is could 348 be low enough to show symptoms?

Gambit62 profile image
Gambit62Administrator in reply to bkerch55

if your normal level is higher than 348 then, yes you would be symptomatic. Unfortunately there is no way of knowing just by looking at you if 348 is the right level for you. It may be that there were other blood tests pointing to B12 deficiency - eg full blood count showing your red blood cells were larger and rounder than normal or your homocysteine levels were raised.

There is a lot more to metabolising B12 than just absorbing it from you food - which is primarily what serum B12 is about. B12 is used in a lot of processes that go on in your cells and there are a lot of genes involved and a lot of polymorphisms on those genes which affect how efficiently those processes run which is likely to be part of why there is such an enormous range for B12.

Your body stores B12 in your liver and releases it as needed to maintain reasonably constant B12 levels in your blood. If you have an absorption problem then your stores get depleted because the B12 is released in bile to be reabsorbed into your blood using the same mechanism that your stomach uses to extract B12 in the first place - so if you have an absorption problem serum B12 levels will fall.

yes,i've had symptoms all my life and b12 was 404 [190.00-910.00ng/L] in april 2018,it is the only time i've known i have been tested for b12

sorry,first time

Interesting! I am assuming they gave you the injections? How fast did you notice it working for you? Did you symptoms sounds similar? I really appreciate the response.

yes i had the loading doses at my surgery ,was'nt offered any more so read the great advice on this forum and have been si for six months,apart from diarrhea ,have had same symptoms as you,i have responded really well to the injections,had what people on here call reversing out symptoms[numb toes for a while,mouth ulcers]but its so nice not to be depressed,brain fogged,fatigued etc,has your doctor prescribed you the loading doses too?

well they had me come in and they gave me an injection in my arm. They said they would call to follow up when I should come in to get another one. She also has me on 1000 of B12 daily under my tongue.

that sounds good,let us know how you get on,it's always interesting to hear how people respond to all the b12 methods of treatment

clivealive profile image
clivealiveForum Support

Hi bkerch55

Anyone at any age, can become B12 deficient. However, certain people are at an elevated risk. They include the following:

Vegetarians, vegans and people eating macrobiotic diets.

People who’ve undergone any gastric and/or intestinal surgery, including bariatric surgery for weight loss purposes (Gastric bypass).

People who regularly use proton-pump- inhibitors. H2 blockers, antacids, Metformin, and related diabetes drugs, or other medications, or infections such as h-pylori that can interfere with B12 absorption.

People who undergo surgeries or dental procedures involving nitrous oxide, or who use the drug recreationally.

People with a history of eating disorders (anorexia or bulimia).

People with a history of alcoholism.

People with a family history of pernicious anaemia.

People diagnosed with anaemia (including iron deficiency anaemia, sickle cell anaemia and thalassaemia).

People with Crohn’s disease, irritable bowel syndrome, gluten enteropathy (celiac disease), Pancreatic insufficiency, or any other disease that cause malabsorption of nutrients.

People with autoimmune disorders (especially thyroid disorders such as Hashimoto’s thyroiditis and Grave’s disease) Type 1 diabetes, vitiligo, lupus, Addison’s disease, ulcerative colitis, infertility, acquired agammaglobulinemia, or a family history of these disorders.

Women with a history of infertility or multiple miscarriages.

Can you "see yourself" amongst any of the above people?

A study coming out of Tufts University showed that 40% of young adults studied had low levels of the vitamin, despite their "healthy" diets. It seems that B12 from meat, chicken and fish is not as well absorbed as we thought; absorption from dairy products is much better. A glass of milk, for example, can yield a microgram of B12. It is also possible that cooking helps to bind the vitamin more strongly to proteins. Some cereals, such as Protein 19, are fortified significantly, but others such as Corn Flakes are not. So regardless of age, it is a good idea for everyone to make sure they take a daily supplement of vitamin B12 and be sure to consume enough dairy products.

The above is but an extract from the article linked below:


I am not a medically trained person.

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