Let’s start with this: B12 is one of the 13 vitamins that your body needs to function. Its most basic purpose is to produce hemoglobin, which allows your red blood cells to carry oxygen throughout your body, including to your brain.

BLOG: B12 for Kids

Vitamin B12 is also necessary for your brain and nervous system to function normally. Without your B’s (and there are seven others of them besides B12!), your body, including your brain, just won’t work right.

Here some quick things to know about B12:

  1. Your body doesn’t make its own B12. It relies on you to eat foods that contain vitamin B12, and to take dietary supplements to fill in the gaps when you’re not getting enough from your diet alone. If you’re deficient, another solution is an oral vitamin B12 (drug) or B12 injections, both ideally recommended with a doctor’s guidance and, if needed, accompanied by a prescription.
  2. And if you think you can eat a 32 oz. porterhouse steak and be done getting your B12 for the week, think again. (Although if you can eat a 32 oz. steak in one sitting, we have a hot dog contest to tell you about!) As it happens, B12 is a water-soluble vitamin, which means two things: first, you can if you want, but you don’t have to, take a vitamin B supplement with food; and second, if you consume too much vitamin B12, your body will excrete most of it in your urine, rather than storing it for future use. So, it’s one of those vitamins that works best on the daily; that’s how you can maintain your optimal levels and therefore your bodily functions. (Although, B12 excretion is not a license to overindulge, because usually too much of a good thing is not a good thing.)
  3. You may not realize this, but if you’re going to fall short on one B vitamin, it’s likely to be B12. Up to 6% of adults under the age of 60 have vitamin B12 deficiency and for those over age 60, the percentage is somewhere between 20% and around 40%. And a vitamin B12 deficiency causes all sorts of bodily issues, including those related to the brain.
  4. If you’ve heard that B12 is known as the energizer bunny of vitamins, here’s the reason why: B vitamins are vital for proper metabolism, as they release energy from food, then help turn the food into fuel, creating energy for your own body’s use.
  5. It’s fine to refer to vitamin B12 by its number, but if you want to be fancy, you can refer to it as cobalamin, its chemical compound name. (Just a little tip to impress your family and friends. You’re welcome.)

VIDEO: 3 Things that Happen When You Don’t Get Enough Vitamin B12


Benefits of Vitamin B12 for the Brain

In 2016, Jane E. Brody, long-time personal health columnist for the New York Times, wrote an article titled “Vitamin B12 as Protection for the Aging Brain.” Among the things she wrote was this: “… based on advice from the National Academy of Medicine and an examination of accumulating research, I’m prompted to consider also taking a vitamin B12 supplement in hopes of protecting my aging brain.”

Now, in fairness to Ms. Brody, we don’t know what her decision was. We do know from the article, that, by her own account, she was getting “ample amounts” in her regular diet of several of the animal protein foods (meat, fish, milk, cheese) that she called “the only reliable natural dietary sources of B12.”

However, at age 75 (at the time), she was concerned about the fact that as people age, the ability to absorb vitamin B12 found in those foods decreases.

It’s an interesting article, worth a read.

When it comes to the benefits of vitamin B12 specifically for the brain, the body of research has been mixed.

For example, this systematic review and meta-analysis, examined the literature for vitamin B12 supplementation in elderly patients without advanced neurological disorders on cognitive function, depressive symptoms and fatigue. Based on pooling results from 16 randomized controlled trials (RCTs) including over 6,000 patients, the authors concluded that their systematic review did not support the use of vitamin B12 for cognitive function and depressive symptoms.

BLOG: Neurological Symptoms of B12 Deficiency

However, one of the study limitations, as noted by the authors was found in the short time frame of the RCTs included in their review, covering treatment durations of only up to two years; therefore, the authors stated that “the question of effectiveness of long-term vitamin B12 supplementation remains unanswered due to the lack of experimental evidence.”

That limitation raises an interesting point. Nutrients are not drugs. So, don’t expect them to act that way. Ideally, you want a lifetime of optimal levels of vitamins to support good health and hopefully longevity. While taking vitamin B12 supplements to improve your vitamin B12 status may find success quickly, it’s realistic to recognize that a short-term vitamin B12 fix may not lead to success in clinical trials.


Effects of Vitamin B12 Deficiency on the Brain

On the other hand, this article points to several studies that show benefit for some aspects of brain health for people who are low in vitamin B12, when their B12 status improves.

For example, in a study in older people with depression whose vitamin B12 levels were at the low end of sufficiency, they were more likely to see improvement in their depressive symptoms when their treatment included both antidepressants and vitamin B12 compared to those receiving only antidepressants.

Another study, this time a large review, found that in older females, a vitamin B12 deficiency was linked to a higher risk of depression.

BLOG: Can You Get Too Much Vitamin B12?

The article also pointed out that vitamin B12 plays a key role in synthesizing and metabolizing serotonin, which is a chemical in charge of regulating mood. Consequently, a vitamin B12 deficiency may lead to decreased serotonin, suggesting a link between B12 deficiency and a depressed mood.

In fact, there is quite a bit of research that ties vitamin B12 deficiency or insufficiency to several brain-related health issues.

This blog—one of ours—shares results from more vitamin B12 (and a couple of the other B’s) studies on the brain and also shares some wisdom on what to make of the studies that don’t show positive results.

VIDEO: How Much Vitamin B12 do you Need?


Vitamin B12 Deficiency: Symptoms and Risk Factors

If you’re concerned that you might be vitamin B12-deficient, or even at an insufficient level, testing is the way to find out. Here are some symptoms that could indicate you have a (lack of) vitamin B12 problem.

  • Fatigue
  • Weakness
  • Pale Skin
  • Loss of appetite
  • Unexplained weight loss
  • Heart palpitations
  • Balance problems
  • Depression
  • Confusion
  • Headaches
  • Cognitive issues
  • Nervous system damage
  • Dementia

If you’re interested in learning more about the neurological symptoms of B12 deficiency, we’ve blogged about it before.

There are many populations at greater risk for vitamin B12 deficiency including:

  • Vegetarians or vegans or other people who are not getting enough (or any) B12 from dietary sources
  • As you age, you are more likely to have trouble absorbing vitamin B12; malabsorption can lead to a deficiency
  • Crohn’s disease and celiac disease may make vitamin B12 absorption problematic
  • Gastric surgeries, including removal of your stomach or intestines
  • Some medications may reduce vitamin B12 absorption or lower blood levels of the vitamin, including metformin, prednisone, hydrocortisone, to name a few; ask your doctor or pharmacist if you are taking any prescription drugs that could interfere with vitamin B12
  • Heavy drinkers


Sources of Vitamin B12

Earlier in this blog, we told you that your body needed you to help it get enough vitamin B12. Now we’re going to tell you how, nutritionally.

Start with your diet. Here are five nutrient-rich food sources containing vitamin B12:

  • Liver—we’re not going to say “yum” on that one, but we’re also not going to “yuck” someone else’s “yum.” Beef liver is about as nutrient-rich with B12 as you can get, with lamb and veal liver not far behind. Actually, some sources claim lamb is generally higher in B12 than beef or veal liver, but how often do you come across, let alone want to eat, lamb liver? In any case, 3 ounces of beef liver has about 70 mcg of vitamin B12, more than your daily value.
  • Meat—beef, especially, gives you a good bang for your buck when it comes to vitamin B12. About 3.5 ounces of a beef short rib or a hamburger gets you about 5.9 mcg of vitamin B12, also more than the daily value. Chicken is another meat that serves up a good source of B12.
  • Clams—where are our shellfish lovers? A serving of 20 small clams comes with very high concentrations of B12, more than 7000% of the recommended daily value. A 3.5 ounce serving contains up to 99 mcg of B12. And the clam broth is also vitamin B12-rich. Other fish sources include salmon (you know we weren’t going to skip that one, what with all the omega-3s and vitamin D) and sardines (we know you’re probably going to skip that one—but your loss!).
  • Eggs—two large ones (about 3.5 ounces get you 1.1 mcg of vitamin B12.) It doesn’t sound like a lot, but it’s close to about half of the recommended daily value for B12.
  • Breakfast cereals—not all of, but certainly the ones that are fortified with vitamin B12. This option could be a good option for vegetarians or vegans. Some cereals will fortify with more vitamin B12 than others—(the label will tell you). And if you add B12-fortified milk to your cereal (or add your cereal to your fortified milk—we’re not judging), you can increase your vitamin B12 intake.

Check out this piece for more tips on foods containing vitamin B12.

If you’re not getting to where you want your vitamin B12 to be, based on your diet alone, that’s where a nutritional supplement comes in. You have options: multivitamins generally contain B12, as do vitamin B12 complex (more than one B vitamin) supplements. There are also numerous single B12 supplements on the market, including those for vegetarians and vegans, ranging in different doses.

You can check your vitamin B12 status—at OmegaQuant we have an at-home test that measures your urine for methylmalonic acid (MMA), a specific indicator of low vitamin B12. Once you know your numbers, you can work with your doctor to be sure your vitamin B12 levels reach sufficiency or optimal range—and stay there.

VIDEO: What is the Desirable Level of B12 in Your Body?

These statements have not been evaluated by the Food and Drug Administration. This test is not intended to diagnose, treat, cure, prevent or mitigate any disease. This site does not offer medical advice, and nothing contained herein is intended to establish a doctor/patient relationship. OmegaQuant, LLC is regulated under the Clinical Laboratory improvement Amendments of 1988 (CLIA) and is qualified to perform high complexity clinical testing. The performance characteristics of this test were determined by OmegaQuant, LLC. It has not been cleared or approved by the U.S. Food and Drug Administration.

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