Vitamin B12 deficiency is a silent epidemic causing symptoms of chronic disease all across the globe. Remember that iconic line from I Love Lucy? “Are you tired, run-down, listless? Do you poop out at parties?” Lucy was definitely onto something as she comically recited her famous “Vitameatavegimin” monologue. As funny as it seemed on the show, the answer to your unresolved health issues may really just be a vitamin deficiency. The well-known Framingham Study estimates that 40% of Americans are not getting enough B12. Countless prescriptions are written each day by well-meaning physicians that, at best, mask symptoms caused by a lack of this essential vitamin. Side effects from these prescriptions often cause even more symptoms, and these medications can further deplete nutrient reserves. This vicious cycle can be prevented. If done properly, reestablishing normal B12 levels is safe and can greatly improve how you feel. 

Do you ever complain of…

• Fatigue, even after getting a good night sleep
• Memory Loss
• Lack of Focus
• Muscle Tension and Aches
• Numbness in your hand or feet
• Emotional Ups and Downs
• Depression or Anxiety
• Male or Female Infertility
• Low Testosterone
• Digestive Issues (leaky gut, IBD)
• Hypothyroidism

…If so, you may have the symptoms of a vitamin B12 deficiency.

Benefits of Vitamin B12

Energy

Vitamin B12, also called cobalamin, is a water-soluble vitamin essential for many critical metabolic pathways. Commonly called the “energy vitamin,” B12 is needed for the proper formation of red blood cells (the cells that deliver oxygen to the entire body). Without adequate B12 (an important DNA precursor), a type of anemia called macrocytic anemia can occur. With this type of anemia, not enough red blood cells are being produced. The RBCs that are being produced end up being too large (macrocytes) and have a hard time delivering oxygen to cells, which the body vitally needs. A lack of cell oxygenation causes exhaustion and extreme fatigue. B12 is also responsible for supporting the adrenal and thyroid glands, as well as methylation, which are all responsible for giving the body the energy it needs. 

Brain and Nervous System

Vitamin B12 helps protect our brains and nervous systems. It’s involved in the production of the myelin sheath surrounding the brain and all of the nerves. Myelin is the insulation that protects the nerves just like the insulation around electrical wire. If the myelin breaks down, the nerves won’t be insulated properly and the signal can get crossed. This can lead to memory loss, cognitive decline, dementia, poor balance, and peripheral neuropathy (pain and numbness in the hands or feet).

Depression 

If you suffer from depression, anxiety, or other mood disorders, a B12 deficiency could be to blame. The medical literature contains more than 460 studies reviewing this connection. B12 is a critical component of the receptors in our brain for the neurotransmitters serotonin and dopamine. If these receptors are not working properly, the body can’t enjoy the mood-boosting effects of serotonin or the pleasure- deriving effects of dopamine. The result? Seemingly unexplainable depression. Many people report being depressed without causation, saying that they simply can’t help it. 

Cancer Prevention

We know vitamin B12 plays an important role in DNA synthesis, and its presence in the body’s cells helps to alleviate the wear and tear on our genetic material. Each time a cell divides, some of the genetic code gets damaged. If this damage goes unchecked, cells can mutate, eventually leading to cancer. Vitamin B12 supports the process of methylation, which helps to repair this genetic damage. Low levels of B12 are specifically linked to increased risk for breast, cervical, and colorectal cancer.

What can cause B12 Deficiency

There are two basic reasons why one can become deficient in B12. The first is from not consuming enough B12-containing foods, and the second is due to malabsorption of B12. Both conditions are actually more common than you may think.

B12 in the Diet

Vitamin B12 is only found in animal products. This means that vegans and vegetarians are at an increased risk of becoming deficient in B12. In fact, studies consistently find that up to 50% of long-term vegetarians and 80% of vegans are deficient in B12.

Top 10 Vitamin B12 Foods

1. Beef and Chicken Liver (550% RDA)
2. Sardines (337.9%)
3. Salmon (236.2%)
4. Tuna (110.8%)
5. Cod (109.1%)
6. Lamb (104.5%)
7. Scallops (101.6%)
8. Beef (grass-fed) (60%)
9. Yogurt (37.9%)
10. Venison (36%)

Absorption of B12

B12 is a large molecule and its absorption is extremely complex. There are several steps and each of them can go awry. The American Journal of Clinical Nutrition explains that “malabsorption of the vitamins from food” is the primary cause of vitamin B12 deficiency.

Causes of B12 malabsorption include:

• intestinal dysbiosis, yeast overgrowth or SIBO
• acid reflux, leaky gut, Crohn’s disease, ulcerative colitis, celiac or IBS
• hypochlorhydria (low stomach acid)
• pernicious anemia and other autoimmune conditions
• medications (especially PPIs, other acid-suppressing drugs, diabetic drugs, and birth
  control pills)
• alcohol
• aging (especially over 60
• lap-band surgery
• fish tapeworms (diphyllobothrium)

This explains why B12 deficiency is common even in people eating large amounts of B12- containing animal products. In fact, many of my patients that are B12 deficient are following a Paleo or Ancestral diet where they eat meat several times a day.

Pernicious Anemia

Pernicious anemia is an autoimmune condition where the body destroys intrinsic factor, a protein made in the stomach that is required for B12 absorption. This condition used to be fatal until researchers discovered death could be prevented by eating raw liver—the richest source of B12 possible. Patients with pernicious anemia or severe gastritis will require B12 supplementation with intrinsic factor added or B12 injections for the rest of their lives.

Tape Worms

In some persistent cases of B12 deficiency that don’t respond to proper dietary supplementation, aren’t helped by addressing an underlying gut issue, and don’t fall into the autoimmune category, a fish tapeworm (Diphyllobothrium) may be to blame. Have you ever eaten raw fish before? For some, sushi is a staple part of their diet. As delicious as it may be, even the cleanest of fish from the fanciest of restaurants may be hosting parasites.  In order to survive, this particular tapeworm feeds on the B12 found in the intestines. In most cases, symptoms aren’t detected until the tapeworm has grown considerably. At this point, extreme fatigue, rapid exhaustion, intestinal discomfort, nausea, and weakness may begin to surface. If you suspect this is the case, a complete blood count (CBC) with differential, B12 blood test, and stool sample are all important labs to consider. Not to worry, tapeworms are treatable. While this isn’t the likeliest cause of B12 deficiency, it is definitely a possibility.

Testing B12

Diagnosing B12 deficiency is not as straightforward as it may seem. The standard blood test measures serum, or plasma B12 levels, and the “normal” value according to the Mayo Clinic should be above 300 ng/L. Levels between 150-300 ng/L are considered marginal, and below150 ng/L indicate a true deficiency. As with many lab findings, the normal ranges set by most labs can be misleading. In the case of B12, there is clear evidence in the medical literature that people with B12 levels between 250 ng/L and 350 mg/L—which may be considered normal by some labs—have clear symptoms of B12 deficiency. According to experts who specialize in the diagnosis and treatment of B12 deficiency, all patients who are symptomatic and have B12 levels less than 450 pg/mL should be treated. They also recommend treating patients with normal B12 levels, but elevated urinary methylmalonic acid (MMA), homocysteine, or holotranscobalamin—all of which can indicate B12 deficiency.

In countries like Japan and Europe, the lower limit for B12 is between 500-550 ng/L. This level has been associated with common signs of aging including cognitive decline, dementia, and memory loss. Some experts have speculated that the higher “normal” limits in Japan explain the low rates of Alzheimer’s and dementia in that country. In stark comparison, most U.S. doctors won’t even second guess, let alone treat, people who show “normal” (sometimes as low as 250 ng/L) levels of B12. 

Increase Your Vitamin B12 Naturally

If you think you might be deficient, or your blood test indicates a deficiency, the best way to fix this is to address the underlying cause for deficiency in the first place. For example, you may need to consume more B12-rich foods if your diet is lacking in them. It could also mean healing your gut, or eliminating certain medications so that you are better able to absorb B12. If you have pernicious anemia you will likely need B12 injections. Finally, it might be necessary to supplement with B12.

B12 Supplementation

Supplementing with vitamin B12 is safe and can help eliminate many symptoms, especially if you use the appropriate forms. Because vitamin B12 is a water-soluble vitamin, it is difficult to overdose or build up vitamin B12 toxicity. There are three common forms of B12 used by most suppliers— cyanocobalamin, hydroxycobalamin, and methylcobalamin.  Cyanocobalamin is the cheapest and most commonly used, but it’s the least effective of the three. I would avoid this source. Hydroxycobalamin, the form most popular in Europe, is better absorbed than cyanocobalamin, but methylcobalamin is the most effective form available. If you choose to supplement with B12, I highly recommend only using a source that has methylcobalamin. In my practice, I prefer to use a sublingual form of methylcobalamin that has intrinsic factor added to it like this one.

While B12 may just be a vitamin, we’re not talking Flinstones Chewables here. B12 is responsible for so many bodily processes and we wouldn’t get very far without it! Before blaming your poor memory or lack of energy on “just getting older,” remember that a B12 deficiency may be the cause of your myriad of symptoms. 

Keep in mind:

• If you’re tired all the time, feel “moody,” have digestive issues, or just can’t seem to focus the way you know you should be able to, it can’t hurt to get you B12 levels checked out. 
• B12 is needed for energy production and brain/nervous system function; it’s also a preventative for depression and cancer.
• B12 is found ONLY in animal products.
• Intestinal malabsorption, pernicious anemia, some prescription medications, alcohol, and fish tapeworms can all be causes of B12 deficiency. 
• Test your B12 levels, but don’t confuse the standard U.S. labs “normal” levels with actual healthy levels. If you’re below 450 pg/mL, you likely need to address a deficiency. 
• Supplement with the most effective form of B12, methylcobalamin.

Have you been treated for a vitamin B12 deficiency, or do you suspect a deficiency? How have you gotten your B12 levels back into a healthy range? Let me know in the comments below!