I am going through b12 deficiency. Its really bad. I had all these symptoms. I was feeling weak and dizzy all the time. Have blurred eye vision. Was not able to stand and breathe properly. My brain was giving me trouble. I use to feel cold even when its very hot. My heart rate and pluse rate was high. Then I got my blood test done. Where my doctor found I got b12 deficiency. Now I am on b12 diet and supplements. Hope I recover soon. Thats for everyone out there. If you feel such symptoms don't neglect them immediately go and see your doctor.

If you are on B12 and are still experiencing symptoms of B12 deficiency, you may not be able to absorb oral B12. A blood test for B12 and methymalonic acid can help determine whether or not you are able to utilize oral B12. If not, consider switching to sub-lingual B12. My nutritionist had me make the switch and it made a world of difference. Within a week, my upper airway was clear and my breathing improved tremendously.

I’ve been on B12 for 2 years, after feeling constantly lethargic and tired every day. And what a difference it has made..

I’m a vegan and recently have been experiencing many symptoms listed in this video. My doctor did some blood work, as it showed my vitamin b12 was very low. He put me on a supplement and three months later, proud to say I’m back at a range rate! I never realized how deficient I was until I began taking vitamin b12 supplement. I now feel much healthier and less cloudy.

1:03 Pale or Jaundiced Skin 1:39 Weakness and Fatigue 2:18 Glossitis and Mouth Ulcers 2:50 Sensations of Pins and Needles 3:35 Disturbed Vision

Thank you for getting straight to the point and not wafting on endlessly

Had all these symptoms. General weakness and lethargy. Blurred vision. Mental fog. Staggering. Intermittent breathlessness. Confusion to estimate depth. Bleeding tongue when brushing. Pins and needles. Changed diet-more boiled eggs, greens, no alcohol, fish, fresh peanuts, fruits, meat etc. Now much better.

I’ve had B12 deficiency for years. My first symptom was being perpetually tired even as soon as I got up after a good nights sleep. Was given iron tablets which did absolutely nothing. Then when I had a small mole removed they did extensive blood work and found the B12 deficiency. Now on B12 injection every 12 weeks and have been for years.

I get B12 injections at my naturopathic doctor's office. He was very hard to find, because most pharmacies who do B12 injections do standard ones with aluminum additives. If you go the injection route, PLEASE make sure you find someone who gives ALUMINUM FREE injections. You don't want to cause more problems than you prevent!

You left out one very important issue. Low b12 can cause dementia like symptoms or complete psychotic break down. I just went through this with my mother in law. She was in the hospital a week. Found wondering around at 1am confused and scared because she thought her phone had been hacked and there were people going to come and kill all her family. They got her b12 back up and she is back nearly to her normal self.

Omg this explains so much. Constant mouth sores and a swollen tongue I thought was being caused by allergies! Thank you!!

Thank you! I asked my doctor about B12, and why my vision would improve after taking it a short time later. He shrugged his shoulders and said he didn't know. I don't think he really believed me. So, when I went to the eye-doctor, I asked her. She had no idea either. All of this occurred after I had jaundice, fatigue and the rest of the symptoms. I'm glad that you have confirmed my insistence of taking B12. Thank you again!

The pins and needles is actually what led to my B12 deficiency diagnosis. I had pins and needles that lasted for long times and occurred even when I wasn't sitting. Went to the doc and he ordered the blood tests because I have a lot of the other symptoms as well and never really thought about it.

I had numb toes and I couldnt walk a straight line people thought I was drunk. It was my neurologist who discovered my low b12 after numerous doctor visits and tests. She insisted I get the injections, my regular doctor refused and just wanted me to take the pills. I fired him and got another one!! Been on the monthly injections for 4 yrs now and I feel much better and I have no more numb toes. My vision gets blurry right before my injections are due. I always tell people now how much low b12 can affect your life, it's worth checking out.

Got sick a month ago, so so sick l wanted to roll over and die, l was so sick l couldn’t get up and extremely nauseous. My doctor who is also my neighbour did my bloods, my results came back with a B 12 deficiency, after the first jab of B12 l immediately started to feel better, now after five jabs lm almost normal. This is a very debilitating illness, everyone should get bloods done in order to check for B12 deficiency. 👍👍👍

I was diagnosed with pernicious Anemia back in 2006. But it took 2 years to diagnosed me. Because it took so long I have permanent nerve damage on my feet and legs. This disease is no joke. Tired all the time

Long term alcohol use (alcoholism) is a frequent cause of vitamin b12 deficiency. Extreme deficiency can cause seizures too. But your commentary was excellent. Thank you.

I’ve ended up in the hospital twice because of b12. I’ve slept more than 30 hours in urgent care. My body destroys b12 so forth I need a shot once week.

This is best b12 presentation I’ve seen on YT.

Turns out I am anemic and it caused awful petechia all over my body. I looked like a monster. Take your b12 vitamins people

I was misdiagnosed with MS at a hospital because I had lost my vision in my left eye. It took a very skilled naturopath that knew what to order on my blood panel to find that I have the MTHFR gene mutation which causes extreme B vitamin and folate deficiency. So happy I looked for outside help. The hospital had me on so much prednisone for no reason. Doing more harm than good. I take a $20 B and folate supplement by integrative therapeutics (available on amazon). Been taking it for years now and I live a normal life and my vision is back. Hope this helps anyone out there struggling to find a diagnosis.

I had all these symptons, doc sent me in for bloodwork, which back it up and turns out I have Celiac Disease! Explains why body could not absorb B12 and other vitamins. Not rectifying it but will be quite a while before I am back to normal. Thanks for this great video!

I got my levels tested and it's way below deficient. I am taking B12 shots and medicine, let's hope I get rid of this deficiency.

Many people with B12 deficiency may have undiagnosed SIBO as it causes damage to the gut lining leading to malabsorption of nutrients. I had the tingling in my feet late last year before I did the breathe test. Now I am on a special restrictive diet to help repair the damage. Already I have more energy and far less digestive issues.

Wow I'm amazed right now. I was diagnosed with fibromyalgia a couple of weeks ago and the nerve pain was unbearable. I took a Dissolving tablet of b12 and I actually feel almost normal.. I feel like crying! Something as simple as a B12 deficiency was causing my symptoms and it felt like my body was dying. Been to the doctor and ER so many times and they never thought to test my B12 levels. Fuck modern medicine!!!

I had a B12 deficiency while on a vegetarian diet. I'm still vegetarian, but now I take supplements and eat fortified cereal, and I do fine.

I was 63 before being diagnosed with lack of intrinsic factor. I wasn’t eating right and it developed into pernicious anemia. I had huge purpose bruises, bleeding gums, hair loss- initially they thought I had leukemia! B12 injections fixed me right up!

The best way to determine whether you have a B12 deficiency, or any vitamin deficiency, is to go to a lab collection facility like Quest Diagnostics and order lab work. It won’t be covered by insurance, but is affordable. You can get B12 checked for less than $50. It’s better to take that approach than to experiment and not really know for sure. And you definitely don’t want to leave things like iron, vitamin D or vitamin E up to experimentation because having too much of those vitamins can be detrimental to health.

For people following a vegan diet, it’s important to not that the only reliable sources of B12 in plants have been found underwater. Duckweed (water lentil) and Chlorella (Algae) have been shown to contain bioavailable sources of B12, however early studies haven’t been as reliable in finding B12 in Chlorella- it has been thought that the early testing methods weren’t as robust as newer methods. The algae Sprinula has also been shown to contain B12, however it has shown to be an analogue source of B12- This can be potentially dangerous. The B12 molecules in Sprinula have a similar structure as B12 found in soil, meat and Chlorella, however, it’s not very well absorbed. This means that it will bind onto the same receptors as B12 blocking other B12 molecules, which are better absorbed, from binding onto these receptors. Whilst Sprinula has a lot of other nutrients that will be absorbed, it is probably best to limit the intake of Sprinula. Duckweed is harder to come by, however Chlorella can be taken in a powder form by itself or in a ‘greens’ superfood powder. One study I read showed that giving individuals who had B12 deficiency 15 Chlorella tablets twice per day helped restore there bodies levels of B12.

it’s not just the elderly who have pernicious anaemia, I was diagnosed aged 30, as was my mother

I’ve been sick for like 2 years… doctors don’t know why… it started with gut problems and I got increasingly worse over time… I have all the symptoms in the video and started using b12 in the morning… my vision has got better, haven’t got the pins and needles in my feet and hands in a week or so… also have a lot more energy… I still get pallor for no reason sometimes but everything else is slowly improving

As we age our bodies decrease production of hydrochloric acid, which is needed for our bodies to metabolize B12 in the food we consume. As a result after age 40 or so, we also cannot process oral B12. This makes sense. The best way to get supplemented now is IV, IM, or SC....I prefer subcutaneous as this is the most convenient and fairly pain free...I am an RN and I teach others how to do this easily and cost effectively...doctors charge too much, it is so unnecessary. I have heard that doctors will charge anywhere from $25-$50 a shot, plus the cost of the visit. I am in Canada and can buy it over the counter for about $ .80 a shot, including the needle. Doctors can get it even cheaper, so this is pure profit for them.

I gotta say, this was "life-changing" for me.

I have every single symptoms. They keep saying it's ms. I started taking 2000 b12 a day so fingers crossed 🤞

Wow, this provides such clarity. I had been attributing my persistent mouth sores and swollen tongue to allergies! Thank you for shedding light on this!

I had a symptom of staggering and loss of balance when walking. My doctor did not know what was causing it and didn't even try to research it. I was told by my Thyroid UK forum buddy to try B12 and I did and it worked.

B12 is absorbed in the last part of the intestine {ileum] to be absorbed the vitamin must combine with intrinsic factor a protein produced in the stomach by the parietal cells. Some patients that have had an ileostomy will experience a gradual decrease of their levels of B12.

I have MS and I think that probably B12 shot can be really helpful so I'm going to ask my doctor about this

I take a powdered supplement with a balance of vitamins and minerals including 1000mcg B12 for five years started feeling weaker and would get tingling feeling sitting too long or would wake up in the night with pins and needles feelings so I started taking 1000mcg B12 with B6 and folate twice a day dissolved underneath the tongue tiredness went away feel stronger and no pins and needles feelings so far.

This might seem weird, but viitamin B12 tablets improved my decision making which led to me quitting a particularly common addiction of our age which I thought was impossible.

Excellent presentation, Joe. Clear, Concise and Confident.

I was 11 when I started getting weird symptoms like my tongue was numb and tingly feeling , I was always tired and I started to lose feeling in my toes & fingers. Then at 16 I was tested for a B-12 deficiency. It was the old shillings test where you take a radioactive B-12 pill and the. Collect urine for 24 hours lol and the results showed I had zero B-12 in my body and couldn’t absorb it, I guess my urine was glow in the dark?. Every woman in my family has pernicious anemia but I was the youngest one ever diagnosed with it. The doctors were shocked and all thought this was only in people over 50.

Thank you. Alcoholic here taking supplements to get back on track. It's terrifying what your brain does when starved of components.

I will straight up say I don't and never have drank alcohol due to how I seen people on it and based on how I was treated as a child due to alcohol. I have pernicious anaemia and I've almost died twice from it. I suffer seriously with concentrating, remembering thing and I gets confused quite often. I get tired easily and get every symptom spoken about in this video. I've now had this 9yrs

Thank you sir. My Dr recommended I take 2 B12 shots a month. To save time and hassle she asked me if I want to do it myself at home. I said ok and now I shoot 2 B12 shots a month. But I haven't noticed any difference in energy since I started, about a year ago. I get plenty of sleep but I still feel tired. BTW, I'm 68 soon to be 69.

Recently, I'm told I have chronic anemia. I remember when I was a child my pedi gave me B-12 shots. I still take B-12 & I'm also told take iron ...which I do. Why can't any of the doc's I've seen over the years tell me what type of anemia I have? What should I be asking them to check in my labs. I thank you for this excellent informative video ...keep up the good work...thanks😀

I read a lot, and sometimes my vision goes blurry and I cant read anymore, so I lay down and close my eyes for 20 mins and its better again.

Excellent information and well presented. Please do more on all the B vitamins.

Stopped eating meat 01/19 Stopped eating dairy soon after. Couldn’t explain the anxiety and depression. Would come out of nowhere. So thankful for this information. I started with b12 b1 and b3 . Not sure how much to take though. I’ll gladly go back to cheese if it’ll curb the anxiety and depression. I have nothing to be depressed about. Any responses or testimonies are welcome. Thanks in advance.

I have B12 deficiency and i can say that there's more things you guys can analyse to see if you have it too! And they are insomnia (there are some cases that of course is a spiritual problem, but in my case it was not), feets that cant be quiet, already move even a little bit without you know (looks like when you're anxious), not a really good memory, in fact you forget the things really easy (almost like Dory hahah :( you forget basic things) and in some cases anxiety and depression (coming to say it again, it could be a spiritual problem, BUT sometimes its just deficiency of B12)

I had serious problems because of b12 deficiency. My left hand and arm had strange sensations and felt like burning. Through MRT they found a lesion in my spinal chord and suggested that i had MS. I recovered completely after supplementing b12!

I have a condition caused by having 2 recessive genes that don't allow me to absorb B12, B complex and folate. To rectify this i have to take METHYL or ACTIVE folate, B12 AND B complex. And I do!

When talking B-12 supplement make sure you also take at least a B-50 complex. That is all B vitamins in one complex(pill) 😊

For those with IF deficiency, oral supplementation is no help-at least in regular doses. Injection would be the best method, followed by the sublingual.

Super helpful. I have lots of symptoms to a lot of things -- and yet doctors seem to always suggest there is nothing wrong -- yet I know my own health and I know what is "normal" for me versus a set of symptoms that are just off the charts for me. I will check out your other videos in case there is something that covers off my own symptoms and sets me on a path of inquiry with my doctors. Thank you :-)

I’ve read that low levels that just scrape over the normal levels are still deficient . B12 is so difficult to obtain in diet for vegetarians. Red meat which I don’t eat is an excellent source . Injections work best as a treatment .

American Academy of Neurology: People with inflammatory bowel disease may also be at risk for developing nerve damage and other neurological problems, according to research that will be presented at the American Academy of Neurology’s 59th Annual Meeting in Boston, April 28 - May 5, 2007. Inflammatory bowel disease includes digestive disorders such as ulcerative colitis and Crohn’s disease that cause swelling and/or bleeding in the intestines. For the study, researchers compared 103 people with Crohn’s disease and ulcerative colitis to 51 people with other digestive disorders, such as irritable bowel syndrome, gastritis and chronic heartburn. The researchers found that those with inflammatory bowel disease were about four times more likely to develop neuromuscular conditions, including carpal tunnel syndrome and small fiber neuropathy, which causes pain and lack of feeling in the feet. Those with bowel disease were also more than six times more likely to also have a disorder called sensorimotor polyneuropathy, a nerve disease that can cause weakness, pain, and numbness. These diseases were more common in women with bowel disease than men. “Inflammatory bowel disease patients commonly suffer from several other medical conditions, like B12 deficiency and glucose intolerance. These nerve conditions we have reported are often not diagnosed by their primary care physicians,” said lead study author Francisco De Assis Gondim, MD, MSc, PhD, Professor of the Federal University of Ceará in Ceará, Brazil, and a member of the American Academy of Neurology. “People with inflammatory bowel disease who develop new symptoms, such as pain or numbness in the feet, should see a doctor.”

Early grey hair is another sign of possible B12 deficiency though it can be some other B vitamin as well

I’ve just been diagnosed with a serious long term deficiency of Vit B12.......after treatment for bowel cancer (colostomy ) in 1994 I have chronic malabsorption....& rely on huge amounts of antispasmodics to try and settle things down. I’ve gradually lost the use of my legs...the chronic pain is unbearable, I also have all these symptoms,coupled with painful neuropathy......stabbing pains disturb my sleep, my eyesight has also deteriorated. At 63 yr...I feel so useless. I urge everyone to check on your vitamin levels.......the Doctors let me down.....23 years of malabsorption..my weight fluctuates between 7- 10 stone........surely the GP should have done something 20 years ago.......but the ‘5 minute,1 problem only’ rule for a GP appointment,hardly gives you time to get your coat off! On top of that..I suffered some serious burns from the radio & live with skin breaking/ infections/ open wounds.....for which I take morphine, which I’m not happy about...but it does help take the edge off the chronic pain.❣️🏴󠁧󠁢󠁳󠁣󠁴󠁿🇬🇧 Pineapple (fresh) is perfect for mouth ulcers. Put some on a cocktail stick & put on the ulcers,regularly......it’s brilliant! I’ve had a course of vit B12 injections..but unfortunately, it had no effect...this can happen. I’m very fortunate,that at last I’ve found a wonderful neurologist,who’s been fantastic,blunt,to the point & like a dog with a bone...never gives up.Its taken 2 decades of gradual deterioration ,endless wasted visits to my GP, for me to finally be referred to an expert & get a diagnosis.......all these symptoms are quite scary & you need a supportive GP...unlike mine!!!

mine hit me so hard at 15 my doctor thought i had leukemia. i lost 20 pounds in less than two months with no appetite. it was so scary. i bruise so easily and lose weight and have appetite issues. plus always freezing. i def dont absorb enough. the fatigue issue has always been serious. i have pernicious anemia.

Would be helpful if you could also recommend natural food sources that can provide Vitamin B12 in our diet - vegetarian/ non- vegetarian / vegan.

I was unable to focus was tired and then got vertigo. I did some research online and found that glocophage which i am taking for prediabetes causes b12 deficiency. I got a blood test done and it was confirmed The doctor had not warned me. I forgot to mention terrible hair loss

I use Garden of Life oral B12 spray....good stuff.

My B 12 was in the very low 300s, my moms was in the 250 region; my mom expressed paresthesia for over a decadeI believe, before I started to experience it. To this day with bi monthly injects (both of us), her flare ups are more frequent. The longer you experience paresthesia, with undiagnosed or not properly treated B12 deficiency, it seems to be harder to get underhand and have relief. Once you have this symptom though... basically the damage is done and you can only prevent it from getting worse. My expression of paresthesia actually wasn't a tingling pins and needles issue, it was a burning feeling mostly at the soles of my feet and the entirity of my toes and occasionally my hands. When my paresthesia was at it's worst, my feet would turned bright red and would radiate heat during a flare up. I occasionally would radiate heat from all over my body actually... not quite as bad now though.

Very informative and helpful. Thank you. Good wishes

I had a swollen and burning tongue, saw some similar information and started a B vitamin complex and it went away within a week.

Did anyone else experience something different from pins and needles? My hand and sometimes arm will get really, really cold, sometimes to the point of hurting. Weirdly, it is usually only my right hand and not my left. I was recently diagnosed as low in B12.

Loud and clear... Thank you for the info sir..

I suffer pernicious anaemia and have b12 injection every 2 months sometimes the injection hurts like hell other time you dont feel a thing, but if your someone whose body dose not produce b12you would definitely start feeling better once you have it, I'd swear that I can feel it working almost straight away, my next injection is the 23 December I consider it a nice xmas present , lol

I've been researching this for a few decades now, since I deal not only with a hereditary insufficiency of intrinsic factor, a substance our stomach normally produces that makes absorption possible, but because I have chronic kidney disease that makes it necessary to reduce protein intake... Normal cooking, even boiling for several HOURS, does NOT destroy B12. It will destroy a fair amount of taurine, though...

I have ulcer all the time that all my relatives and friends confuse why I always get ulcers. Since I eat green salad everyday, my ulcer suddenly gone.

I suffer with malabsorption due to having to take Omeprazole as I have a hiatus hernia. As a result, I have to have a vitamin B12 injection every 12 weeks.

B12 is produced by microbes found in soil and water. Our ancestors would of gotten plenty of B12 from a stream, lake, and dirty soil found on plants. We live in a chlorinated world now, hence why there is so much B12 deficiency.

I had to start B12 injections once a month after gastric bypass, so 20 years now.

I've taken antacids for heartburn for years, and I've just discovered my b12 and folate are both "sub-optimal". I thought for decades i just had "honey" coloured skin, now i realise its probably a bit yellow. Plus the other symptoms too Thank you for this video, if it wasn't for videos like this on youtube, i would have continued on thinking my "chronic fatigue syndrome" was just something i had to put up with for the rest of my life.

Not only elderly people can have percinous anemia , i was diagnosed 6 years ago , also can taking suplements mask a malabsorbtion because it gives false blood results

Interesting since many if not most can also be caused by other deficiencies and problems. Jaundice is usually caused by liver failure, hepatitis. pins and needles is commonly caused by potasium deficiency also (in my case it was). Blurry vision can be caused by a zinc deficiency. Mouth ulcers by zinc, iron, B1, B2, B6. Neurological issues are common with copper deficiencies. Zinc deficiencies also causes neurlogical issues and periphreal neurapathy. Take care in assessing your symptoms with causes. Atleast B12 is very easy to suppliment, just a couple of drops under the tounge or almost any energy drink.

I have been getting B12 injections every 2 months for over 20 years due to being diagnosed with Pernicious Anaemia- hereditary in the family- took 6 months of various symptoms, constant tiredness, scalp sores and gland lumps which was the most concerning, before diagnosed but know now when due for my injection when I get the pins and needles. Had a Doctor recently try and tell me it's not critical to miss having the shots - I had to educate him, even though was recorded on my records of my history and condition- he didn't like being unable to have the upper and so I found another Doctor to treat me 😤

You can also get b12 from fermented foods such as kimchi and kombucha

Doesn't too much alcohol deplete B 12 too?

Get the shot weekly as methylcobolomin b12. Get it with magnesium for extra nutrition and pain relief. In a shot. Costs about $35 for the shot. Worth it. shot needs to be a methylcobolomin.

In certain people, oral supplementation of B12 is not sufficient. I'm one of those "lucky" people. I inject B12 (2cc) once per month and it made a big difference.

The metformin thing wasn't explained, unless I missed it? Important since 2-3 of these symptoms are also shared with diabetes, for which metformin is a very common treatment.

Chemotherapy can cause this also. I have to be on b-12 injections for the rest of my life due to chemo induced neuropathy

Very good and helpful !!

Man I was feeling drowsy weak tired no motivation, took b12 boom I’m back wide open and ready ❤

Can please someone who has recovered from b12 deficiency,tell how much time it took to recover?

I always thought pins and needles feeling in feet, legs, arms, and hands was normal. I had really bad allergies that caused asthma attacks that I never had before. I went to get checked at the hospital and they took blood tests to check for anything unusual. That’s when I found out I have B12 deficiency. I don’t get dizzy but sometimes I stagger into walls or stagger from side to side going up stairs. I guess it affects your balance too. I feel sleepy all the time too and my friends used to make fun of how often I sleep 😅. I’m a young guy but when I think of going on adventures and traveling I get exhausted. Hopefully I can do the stuff I want when I get this under control

Amazing video, will make the protein ball right now!

Thank you for succinct and direct presentation highlighting symptoms that are most common and for the people that say check lab, most physicians are required to have an indicated symptoms or group of symptoms which then are coded and validate the test or tests being ordered. No symptoms, no codes, then CMS or Medical Insurance refuses to pay. Usually labs will require the appropriate diagnosis code for each test before they will do any lab test. Therefore the first step in process is usually detection of symptoms usually resulting in change of energy or outward symptoms such as mouth sores before we will be motivated to remember and report it to physician. Thank you for being succinct and using lay terms. I have worked with many docs…patients and caregivers still clueless after physician explained using Latin descriptors and speaking like giving lecture to peers or last year medical students. And some people spend so much time just talking forever to say what only needed a brief comment, they are totally self absorbed…also providing written description as you explain is great communication and teaching tool. Thank you!

Arthritis can be one of the earliest symptoms of a b 12 deficiencty

At least I learnt something new. Thank you sir.

Thank you- very informative.

How long does it take for symptoms to subside? I was hospitalized because my blood count reached zombie level and my while blood cells were low. They discovered that i had a b12 deficiency and have to take injections because of the malabsorption problem. I was relieved but most days i still feel like death. I shivered all day today with 2 sweaters on and i live in the tropics

I'm into week 4 of giving myself B12 injections. Sadly this is the fifth time my B12 levels have been so low that I e had to do the injections.

Fortified nutritional yeast is the best form of b12 and best absorbed.

Don’t know if some of these symptoms are from my chronic Illnesses or B12 deficiency. Getting a blood test tomorrow though

Thank you for this informative video.

I thought vitamin B12 was found in soil. Don’t animals get B12 through the plants/soil that they ingest? They don’t have B12 unless they ingest it, right?

If you have B12 symptoms but your first test back normal or low, get these additional tests: 1. The Full Blood Count (or FBC) but remember only around 60% of patients with a B12 deficiency will have enlarged red blood cells (macrocytosis). Another problem with relying on the MCV to indicate a B12 Deficiency is that if the patient also has an iron deficiency that deficiency will lead to a reduction in the MCV - an iron deficiency and a B12 deficiency will in effect cancel out each deficiency’s effect on the size of the red blood cell 2. Serum Holotranscobalamin (HoloTC) - The ‘Active’ B12 Test 3. Plasma Methylmalonic Acid (MMA) 4. Plasma Total Homocysteine (tHcy) 5. Red Blood Cell Folate (RBC folate) and Serum Folate KEEP IN MIND with Folate test: The current test does not distinguish between the active and inactive forms of B12 and so if a patient is deficient in folic acid, he or she will not be converting the inactive forms of B12 into the active forms. The result will be that the patient’s B12 status will show normal or high, but very little of this B12 will be in the active form. If the patient has been supplementing using folic acid tablets (as pregnant women are advised to do) then the increase in folic acid will prevent the red blood cells from becoming enlarged (megaloblastic) as discussed above. Therefore, high folic acid levels mean that one of the indicators of low B12 (enlarged red blood cells) will not be present when doctors interpret the results of any full blood count.Also, low level of folic acid has the surprising effect of increasing the amount of B12 loss in urine. The lower the patient’s folic acid, the more B12 will be excreted via urine6. And finally, a healthy level of folic acid is needed to enable the patient to convert any cyanocobalamin (a form of injectable B12) to convert to Hydroxocobalamin and then to the biologically ‘active’ forms of B12 - Methylcobalamin and Adenosylcobalamin. If you have been supplementing your diet using folic acid tablets you should tell your doctor this before or after you have given blood to be analyzed 6. Ferritin (iron stores) Iron plays an important part in the formation of healthy red blood cells and so it is useful to ascertain the patient’s iron stores. Low iron can be the result of hemorrhaging following an accident or from heavy menstruation among other causes THEN, IF YOU HAVE BEEN IDENTIFIED AS HAVING A B-12 YOU SHOULD THEN TEST FOR "PERNICIOUS ANEMIA" Tests for Pernicious Anemia. When a patient is identified as having a deficiency in vitamin B12 the cause of that deficiency should be investigated. These are the tests used to determine whether the deficiency is caused by the patient having developed Pernicious Anemia: 1. Anti-intrinsic Factor Antibody Test 2. Parietal Cell Antibodies Serum Gastrine All of the above can be found on the pernicious anaemia society .org website. In the end, if you suffer from neurological symptoms and you've done an extensive B12 blood work up and you were not found B-12 deficient, read up on Celiac Disease as well as Gluten Insensitivity. Quote: While celiac disease symptoms are often associated with the gut, they can actually go well beyond that. Some scientists now suspect that the autoimmune firestorm ignited in the gut may descend on other organs, including the brain. According to the article, around 10 percent of people with celiac disease, and possibly more, are thought to suffer neurological symptoms, ranging from headache and nerve pain, to ataxia and to epilepsy. Multiple Sclerosic and other types of illnesses can also be a cause. Best of luck.