# How did my B12 get low? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 12, 2017, 3:20pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446 "2017-08-12T15:20:20Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 12, 2017, 3:20pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/1 "2017-08-12T15:20:20Z")
> [@MyChart](#): > > Dear Mr. **zone** , > Your blood sugar, kidney, electrolytes, iron, and blood count tests were all normal. > You are not anemic. > Your Vitamin B12 level was slightly low. The optimal level is above 400. This can cause fatigue. I recommend that you buy over-the-counter Vitamin B12 and take 1000 units daily > (name redacted), MD > > 8/8/2017 11:56 AM > Component Results > Component Value Ref Range & Units Status > Vitamin B12 357 181 - 914 pg/mL Final Causes of Vitamin B12 deficiency: > [@WebMD](#): > > With age, it can become harder to absorb this vitamin. It can also happen if you have had weight loss surgery or another operation that removed part of your stomach, if you drink heavily, or if you’ve taken acid-reducing medications for a long time. > > You may also be more likely to develop vitamin B12 deficiency if you have: > > Atrophic gastritis, in which your stomach lining has thinned > Pernicious anemia, which makes it hard for your body to absorb vitamin B12 > Conditions that affect your small intestine, such as Crohn’s disease, celiac disease, bacterial growth, or a parasite > Immune system disorders, such as Graves’ disease or lupus I’m 63, so age might be a cause, but I stopped drinking heavily months ago, I eat meat, and the other factors are not present. OTOH, I’m 63 so I’m more likely to both experience and enjoy the hallucinations possible from taking 1000 mikes (a metric shitload) of B12, so it’s off to [Wally World](https://www.walmart.com/ip/Nature-s-Bounty-Vitamin-B-12-1000-mcg-Tablets-100-ea/576004513?wmlspartner=wlpa&selectedSellerId=1150&adid=22222222227076917803&wmlspartner=wmtlabs&wl0=&wl1=g&wl2=c&wl3=189588717008&wl4=pla-296399482038&wl5=9021527&wl6=&wl7=&wl8=&wl9=pla&wl10=112549851&wl11=online&wl12=576004513&wl13=&veh=sem) for me! Ew, they have 5000mcg pills, too. That seems a bit much. ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 12, 2017, 3:22pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/2 "2017-08-12T15:22:47Z")
Eek! My deficiency has caused me to put this in the wrong forum! Maybe I need the 5ks. Reported ---
**Author:** ![Sattua](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sattua/32/11906_2.png) [@Sattua](https://boards.straightdope.com/u/Sattua)\ **Post date:** [August 12, 2017, 3:33pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/3 "2017-08-12T15:33:18Z")
People’s ability to absorb it drops as they age. It’s a pretty common diagnosis, and if taking a pill every day fixes it, then your case is fairly mild. I was given the same diagnosis at age 31, fwiw. Sometimes life just ain’t fair. ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 12, 2017, 4:57pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/4 "2017-08-12T16:57:19Z")
Um, I mentioned it can cause hallucinations at six bux a jar. Where’s the unfair? 😉 ---
**Author:** ![Miller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/miller/32/481_2.png) [@Miller](https://boards.straightdope.com/u/Miller)\ **Post date:** [August 12, 2017, 8:37pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/5 "2017-08-12T20:37:34Z")
Moved to IMHO. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [August 16, 2017, 8:01pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/6 "2017-08-16T20:01:30Z")
In my case, I just don’t absorb it in my gut like I should. There is an active transport in your small intestine that grabs the B12 and brings it in, but mine doesn’t work. So I have to take large doses so that enough can be absorbed passively. I’m bad enough that I would have to take shots if the pills hadn’t worked. ---
**Author:** ![Athena](https://avatars.discourse-cdn.com/v4/letter/a/35a633/32.png) [@Athena](https://boards.straightdope.com/u/Athena)\ **Post date:** [August 16, 2017, 8:07pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/7 "2017-08-16T20:07:54Z")
I was officially diagnosed with pernicious anemia at the same time I developed T1 diabetes. At the time, the endocrinologist told me I’d need monthly B12 shots for the rest of my life. Talking with my primary care doc, he said he’s had good luck with daily pills, so we went that route. They work fine. I had no idea it was potentially fatal until the old dude on Downton Abbey got it. He’s like “I’ve got pernicious anemia, I’m dying!” and I was like :eek: ---
**Author:** ![Sattua](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sattua/32/11906_2.png) [@Sattua](https://boards.straightdope.com/u/Sattua)\ **Post date:** [August 16, 2017, 11:13pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/8 "2017-08-16T23:13:04Z")
> [@BigT](#): > > I’m bad enough that I would have to take shots if the pills hadn’t worked. … But the pills _did_ work, ergo you \*aren’t \*bad enough to need shots? ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [August 17, 2017, 12:05am UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/9 "2017-08-17T00:05:34Z")
> [@dropzone](#): > > OTOH, I’m 63 so I’m more likely to both experience and enjoy the hallucinations possible from taking 1000 mikes (a metric shitload) of B12, so it’s off to [Wally World](https://www.walmart.com/ip/Nature-s-Bounty-Vitamin-B-12-1000-mcg-Tablets-100-ea/576004513?wmlspartner=wlpa&selectedSellerId=1150&adid=22222222227076917803&wmlspartner=wmtlabs&wl0=&wl1=g&wl2=c&wl3=189588717008&wl4=pla-296399482038&wl5=9021527&wl6=&wl7=&wl8=&wl9=pla&wl10=112549851&wl11=online&wl12=576004513&wl13=&veh=sem) for me! > > Ew, they have 5000mcg pills, too. That seems a bit much. I personally don’t: I was on 5-6000% RDA for awhile but then I bought 1200mcg sublingual in case I needed all of that and fall behind for a few days. It doesn’t do anything for me personally except to make my mind notice the edges around objects more but I think that’s just going back to normal since before I was diagnosed everything seemed very foggy in that way but changed immediately upon taking my first pill. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [August 17, 2017, 12:25am UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/10 "2017-08-17T00:25:18Z")
Not sure your B12 _is_ low. Why did the doctor test your B12 level? Do you have any symptoms of, well, any kind? We know you do NOT have megaloblastic/macrocytic anemia (pernicious anemia, caused by a relative lack of intrinsic factor due to it, or the stomach cells that produce it being attacked by the body’s own immune system, and thus not being able to absorb oral B12 well, being one cause of). Do you have a peripheral neuropathy or some neuropsychiatric symptoms? “Optimal” is, IMHO, frankly, an “off” and misleading word to use in this context. The level is per the report in the normal range. Most people with numbers in the normal range are not deficient although a few functionally _can_ be. An older adult with a lowish normal range result _who has symptoms consistent with B12 deficiency_ may, upon further testing, be demonstrated to actually have functional B12 deficiency … or may not. The individual _without_ such symptoms, or only with very vague and non-specific symptoms … much more likely not … but testing for functional deficiency (plasma homocysteine level possible also with methylmalonic acid level) would not be unreasonable to do. If those are normal then B12 is already functionally “optimal” and levels are not low. And some may decide that given that there is little proven risk to 1000 mcg/d of oral B12 to just have the asymptomatic or vaguely symptomatic person just take the 1000 mcg B12 daily. If you _are_ actually functionally low it indeed may just be age. The stomach lining can thin with age and cause poor absorption of B12. ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 17, 2017, 1:38am UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/11 "2017-08-17T01:38:58Z")
> **[9 Signs You're Not Getting Enough B12](https://www.prevention.com/health/a20486443/signs-of-b12-deficiency/)** > > Do you have a B12 deficiency? Here's how to tell. Yeah, it’s Prevention and I’ve had a laugh or two at Old Man Rodale’s predictive abilities, but it was easy to find. In the past year or so I’ve been prone to feeling dizzy, even while lying down. Among other things, the B12 recommendation came out of that (see the report in the OP). As a longtime believer that if some is good, more is better, and too much is just right, I’ve doubled the dose for the first week. No reduction in dizziness, but my permanent shaking is a little better. Don’t know if it’s related. No peripheral neuropathy, just carpal tunnel syndrome. Following my EMG that I hoped was looking for something else my MD said that it looks like I have carpal tunnel from a pinched nerve in my elbow. “I pinched it on the last Tuesday in January, 2012.” “So this test was a waste of time and money.” “Yeah, and I could’ve told the neurologist if he had asked, or even explained the test and why he ordered it.” ETA: During the test the doc administering it said, “Oh, that’s not good.” “What’s not good.” “Your neurologist will explain.” Which he didn’t so I had to get the “bad” news from my MD. ---
**Author:** ![ZipperJJ](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zipperjj/32/211_2.png) [@ZipperJJ](https://boards.straightdope.com/u/ZipperJJ)\ **Post date:** [August 17, 2017, 5:58am UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/12 "2017-08-17T05:58:06Z")
If you stopped drinking heavily months ago, couldn’t your “kinda low” B12 be the result of your B12 level coming up after being low from drinking heavily? ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [August 17, 2017, 2:13pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/13 "2017-08-17T14:13:27Z")
> [@dropzone](#): > > … In the past year or so I’ve been prone to feeling dizzy, even while lying down. Among other things, the B12 recommendation came out of that (see the report in the OP). As a longtime believer that if some is good, more is better, and too much is just right … Okay, one of the more vague and non-specific symptoms. I know that the “more is better” bit is meant humorously but when it comes to supplements many do believe that literally. It must be noted that it often is very not true: more may be worse. There is, as I stated, “little proven risk” to the level of B12 supplementation being discussed here, but there is [some strongly suspected](http://jamanetwork.com/journals/jama/fullarticle/184898). Placebo controlled study supplementing B12 and folate together, so not just B12 alone, but risk of death all causes over the next several years increased by 18%, biggest contributor being lung cancer. > [@](#): > > … A total of 136 (4.0%) who received folic acid plus vitamin B12 vs 100 (2.9%) who did not receive such treatment died from cancer (HR, 1.38; 95% CI, 1.07-1.79; P = .01). A total of 548 patients (16.1%) who received folic acid plus vitamin B12 vs 473 (13.8%) who did not receive such treatment died from any cause (HR, 1.18; 95% CI, 1.04-1.33; P = .01). Results were mainly driven by increased lung cancer incidence in participants who received folic acid plus vitamin B12 … Now putting that into some perspective - the big driver of lung cancer is tobacco smoke exposure. _Without_ that historic risk factor the risk of lung cancer is very small and if there is real functional deficiency and/or real benefit supplementation may be worth it. I’m not your doctor and am giving no specific advice. But the belief that many have that “it couldn’t hurt” or that “more is better” does deserve some pushback. ---
**Author:** ![Kimballkid](https://avatars.discourse-cdn.com/v4/letter/k/b5a626/32.png) [@Kimballkid](https://boards.straightdope.com/u/Kimballkid)\ **Post date:** [August 17, 2017, 3:25pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/14 "2017-08-17T15:25:57Z")
Many years ago, I went to the doctor because I was feeling tired all the time. He diagnosed low B12 and I’ve been on the once-a-month shots ever since. I used to go to the clinic to get them because I hate shots/needles but that was getting too expensive so I sucked it up and give them to myself now. I found the secret is to get the ultra-thin needles. ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 17, 2017, 10:37pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/15 "2017-08-17T22:37:30Z")
> [@DSeid](#): > > Okay, one of the more vague and non-specific symptoms. I know, but I use a cane to make me a tripod. I can’t look directly overhead for more than a few seconds without nearly falling over. I have always had poor balance; my big brother\* once asked if I can walk in the dark. “Total darkness? No, but if there is something I can see that I can use as a horizon I’m fine.” “Not surprising considering all the inner ear infections you had as a kid.” I have a referral to someone Doc thinks can help, some sort of PT. - - If you’ve read that before you can ignore it. ---
**Author:** ![IvoryTowerDenizen](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ivorytowerdenizen/32/17937_2.png) [@IvoryTowerDenizen](https://boards.straightdope.com/u/IvoryTowerDenizen)\ **Post date:** [August 17, 2017, 10:42pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/16 "2017-08-17T22:42:42Z")
Do you take glucophage/metformin? That can drop your B12 levels ---
**Author:** ![dropzone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dropzone/32/7515_2.png) [@dropzone](https://boards.straightdope.com/u/dropzone)\ **Post date:** [August 17, 2017, 10:49pm UTC](https://boards.straightdope.com/t/how-did-my-b12-get-low/793446/17 "2017-08-17T22:49:33Z")
Nope. Distressingly healthy for an old fat guy with asthma. And don’t tell Doc **DSeid** that my O[sub]2[/sub] level hovers around the 90-92 level or he’d have me dragging a green tank everywhere. 😃