What You Need to Know About Vitamin B12 Deficiency

Updated on April 5, 2019

When it comes to vitamin deficiencies, most people's knowledge stops at knowing that a severe lack of vitamin C causes scurvy. Maybe some people know the connection between vitamin D, sunlight, and depression. But vitamin B12 is one of those vitamins that people see all the time in pill form on pharmacy shelves, likely know it's important to have, but don't know what can happen when your body lacks it.

A few years ago, I was diagnosed with severe vitamin B12 deficiency. It's not an exaggeration to say that the doctor who checked for it, diagnosed it, and began treating me for it saved my life. Make no mistake; vitamin B12 deficiency can be deadly. It might take decades to be deadly, but it can get that bad, and it will slowly disable you along the way. This can be a scary condition, and I find too few people know about it, which is why I wanted to take the time to help get information to people who may need it.


What is a Vitamin?

First, we need to understand what a vitamin is. Simply put, a vitamin is an organic molecule that we need in order to stay alive but that out bodies are incapable of making in their own. We can't produce our own vitamin A, B, C, or any other letter. We typically get them from the food we eat.

Different vitamins come from different sources. For instance, vitamin C is found in high quantities inside citrus fruits like oranges or lemons, and vitamin D can be found most often in fungi (mushrooms) o), fatty fish, or egg yolks. Vitamin B12, which I'll be talking about today, is most commonly found in red meat, such as beef.

What Does Vitamin B12 Do?

Vitamin B12 is responsible for 2 main processes in the body. First, it's integral for forming myelin, which is the sheath that coats nerves and allows signals from the brain to move along those nerves smoothly. Without B12 to help form the myelin sheath, damage to the myelin cannot be properly repaired, the sheath degrades, and nerves don't function properly. This is similar to what happens in multiple sclerosis, though the process is a bit different in the case of MS.

Vitamin B12 is also essential for making sure your red blood cells, which develop in your bone marrow, can form and mature properly. Red blood cell carry oxygen all over your body, and if they are not mature or don't function properly, then you become anemic, and your organs (including your lungs) will not be able to get the oxygen they need to function properly.


How Much Vitamin B12 Do We Need?

We don't need very much of each vitamin in order to stay reasonably healthy (at least, as healthy as those vitamins can help us to be). Adults need between 2 and 2.4 micrograms a day. We don't absorb all of the vitamins we consume (some naturally get destroyed during the digestive process), but even so, you can get as much vitamin B12 as you need by eating a couple of mouthfuls of ground beef a day. That's all. We don't need very much.

Our bodies can store about 2-5 milligrams of vitamin B12 in the liver and muscles, so if we eat more than we need, we store it for times that we can't get as much. If your bodies stores of B12 are full, you can go for a few years without consuming any at all, and you won't suffer any ill effects from it. Your body will slowly release what it has stored so that you can stay as healthy as possible.

What causes B12 Deficiency?

There are a few different things that can cause vitamin B12 deficiency. The most obvious one would be if you don't eat any and your body runs out of what it has stored. This is rare for most people, since we can store so much and generally need so little, though it is something that vegetarians and vegans should be careful of. Vitamin B12 can be found in certain seaweeds and fermented foods, but there's far less of it than in meat, and our bodies don't absorb it as easily.

For most people, the stomach releases something called intrinsic factor, which is how B12 is processed and absorbed. In some people, however, the stomach doesn't do this properly, or at all, and so the main way we process B12 is absent. No matter how much people with intrinsic factor deficiency consume, their bodies cannot make use of what they are eating. They will go through their bodies stores of B12 and then won't get any more, leading to B12 deficiency over time.

(This is most likely what happened in my case, by the way.)

Sometimes, there are intestinal parasites in a person, and those parasites absorb the B12 before the human body can. Again, no matter how much you eat, your body won't be getting what it needs. This is rare in the developed world, though, as parasites are often found and treated before they interfere with B12 absorption too much.

If your intestines have been damaged due to celiac disease, for instance, that can affect how well your body absorbs vitamin B12. Sometimes people have part of their intestines removed for a variety of reasons, and this can cause the same problem.

How is Vitamin B12 Deficiency Detected?

B12 deficiency can be found with a very simple blood test. 1 vial of blood, sent to a hospital's lab, and a few days later you'll get the result.

Normal B12 levels in the blood are between 200 and 900 nanograms per millilitre, which is fancy medical speak for "a really tiny amount in a slightly less tiny amount." At 200, you definitely have low B12, and there's no dispute. But people often experience mild symptoms when their levels hit 500, and doctors will often recommend taking a B12 supplement at that point, usually a pill.

What Are the Symptoms on Vitamin B12 Deficiency

There are lots of symptoms you may experience, and a lot of them are very common to a number of other conditions. Fatigue is the most common symptom, which is caused by the anemia due to immature red blood cells. You may also experience memory problems, depression, and an inability to focus that is most commonly called "brain fog."

You might lose your balance or have difficulty with coordination. You might develop pins and needles for no reason that you can understand.

These are the most common symptoms, and also the least scary ones. In severe cases, there may be nerve damage, which may never go away. As signals can no longer be conducted from your brain to other parts of your body via your nerves, you may lose your ability to walk, or stand, or move the way you want to move. You might lose control over your bowel and bladder. Your spinal cord may deteriorate. You may experience mood swings, even dementia.

Syringe filled with 0.5 ml of injectable vitamin B12.
Syringe filled with 0.5 ml of injectable vitamin B12. | Source

Is Vitamin B12 Deficiency Treatable?

Yes! Now that I'm done terrifying everyone with scary symptoms, yes. It is treatable. It can always be treated, so far as I am aware!

Sometimes the treatment might simply be the reintroduction of foods that are rich in B12, if the deficiency was caused by, for instance, someone being vegetarian or vegan and not supplementing their diet with the things they need.

If the problem is parasites, then the parasites can be killed and/or removed and they will stop stealing all the B12 you consume.

If you have intrinsic factor deficiency, then your options are to either take a pill that dissolves under your tongue (it's absorbed more easily when it's low-density, the way a dissolving pill provides), or to received injections of liquid B12 on a regular basis. Typically a doctor or nurse will give you the injection, though depending on your situation and competency, you might be free to give yourself the injections instead. (Speak to your doctor before making that decision, though.)

That being said, while B12 is very treatable, that doesn't mean all the symptoms will go away once treatment begins and your B12 levels stabilize. Sometimes, nerve damage is permanent. Depending on how severe the damage was before treatment began, you might be dealing with some issues for the rest of your life. Usually the lingering damage is to the brain and nervous system, since the bone marrow repairs itself very quickly, as do blood cells.

Personal Experience with Vitamin B12 Deficiency

When I was diagnosed with B12 deficiency, my doctor said I had probably been incapable of absorbing vitamin B12 for around 2 decades, meaning that the problem, for me, started in my early teenage years. B12 deficiency is a very slow thing, taking years to get bad, and I blamed myself for a lot of my problems. I was tired a lot, because I was lazy. I couldn't beat depression, because I was worthless. I had hearing problems, balance problems, memory issues, but I was sure a lot of those would go away if I just tried harder.

Or something.

My balance, by the end, was terrible. I would stumble a lot. I was terrified of going out of the house alone, in case I stumbled into traffic and got hit by a car. I would walk into doorways, thinking I was walking perfectly straight. To me, it looked and felt like the world suddenly shifted 2 feet to the side, only without me moving with it, and BAM, suddenly a doorway was in my face! To other people, it looked like I suddenly lurched to the side.

My lack of balance caused me to fall, and sometimes I fell badly. I slipped on the ice at one point and landed hard on my left knee. To this day, I have nerve damage where I fell. The only sensations that place can convey are numbness, and screaming pain if anything puts pressure on it. Sometimes if my body is warm, such as after a hot bath, that part of my leg feels entirely different from the rest of my leg, because the nerves just aren't working properly.

When my doctor gave me the diagnosis, he made things very clear to me. I was about 5 years from being in a wheelchair, maybe 15 years from dying, if things continued as they had. Mine was a very severe case. I mentioned that B12 levels in the blood can range from 200-900 nanograms per milliltre, though 200 is the very lowest end of the "normal" range and typically requires immediate treatment, and often people start experiencing symptoms once they hit the 500 range.

Mine was 93.

I began getting injections of B12. Within 2 weeks, I noticed my energy level improving drastically. I could do things that I hadn't done in years, things that I was so used to leaving me too tired to do anything but rest for a day to recover. Within a month, I had stopped stumbling. I have never again had a doorway jump out at me.

However. I was one of those people who had been damaged to the point that there was no full recovery.

I mentioned the nerve damage in my leg. I still have balance issues, and I walk with a cane to provide me extra stability. I don't stumble anymore, typically, but I feel very off balance if I don't have that extra support. That will probably never change.

But honestly, it could have been far worse. Had I let my discomfort of doctors and my own self-hate keep me from going to a doctor in desperation and saying, "I think there's something wrong with me, help me," I might have gone untreated for far longer. Had I not gotten lucky enough to find the one doctor in the city who was seemingly obsessed with vitamin B12 (he bragged to me about his B12 levels), I might have gone untreated for far longer. I'd seen other doctors before, for other issues (some that turned out to be related to B12 deficiency in the end), and none of them had checked for it.

In fairness to them, I didn't fit the typical profile of somebody who might have a B12 deficiency. I wasn't vegetarian or vegan. I'd never had surgery on my intestines. I didn't have celiac disease. I likely didn't have damage to my intestines, or a bacterial overgrowth there that could be interfering with absorption, because usually those things come with malnutrition and weight loss, and I was overweight. Nobody had any reason to think that I might have intrinsic factor deficiency. So it wasn't tested for.

And that could have killed me.

I got very lucky, and I am so very thankful that I got lucky. Things could have ended so much worse for me. I could, at this moment, be in a wheelchair, unable to stand or walk as my spine collapses in on itself and I struggle to breathe due to ongoing anemia. I could be looking at the future as nothing but a slow decline until an early death. But I'm not. I take my injections to keep my B12 levels where they should be, and I may need a cane to walk, but B12 deficiency is no longer killing me.

It's that luck that makes me want to spread the word about B12 deficiency, what it is and how it manifests, and to encourage people to talk to their doctors about it if they suspect that they might have a similar issue. If you're experiencing the symptoms I mentioned, it may NOT be B12 deficiency, but a quick blood test can tell you that for sure, and then that's ruled out. If it is B12 deficiency, then you can treat it before it becomes too severe. Even if I don't save lives, hopefully I can at least educate and inform.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

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