The Vitamin B12 Connection

Our general health relies on many different factors. From a healthy diet and lifestyle, to our genetic make-up and environmental factors, all are at play. The focus of this newsletter is vitamin B12, one of the thirteen essential vitamins that our body needs in order to stay alive.

While the vital connection between vitamin B12 and hormone balance has yet to be fully understood, growing evidence indicates that we should be cognizant of the importance of B12 in that many disorders associated with hormone imbalances also are dependent upon the effectiveness of B12.

B12 Basics

Vitamin B12 is considered unique in that it is the only one of the thirteen essential vitamins that contains a trace
mineral called cobalt. Hence, it is sometimes referred to by its scientific name, cobalamin.

Another characteristic that sets B12 apart is its natural source. B12 is produced only in the gut of animals, so unlike other vitamins, we can't obtain it from plants or from sunlight.

The best sources of vitamin B12 in our diet include meat, poultry, fish, eggs, shellfish, milk and most dairy products. We can also ensure that we get the recommended amount of B12 in our diets by eating foods fortified with B12 or taking vitamin supplements.

Because B12 is water-soluble, it is not stored easily in our body; rather, it must be replenished daily. If we do not get enough vitamin B12, or our B12 supply dwindles, or we have a greater need for B12, a deficiency in this essential vitamin may occur.

Fortunately, our body usually requires only a very small amount of B12 each day. The recommended daily allowance is 2 to 4 micrograms, which is about the same as one millionth of an ounce.

According to the book Could It Be B12?, co-authors Sally Pacholok, RN, and Jeffrey Stuart, DO, state that many people associate a deficiency in B12 with vegetarians or vegans who fail to eat foods with B12, but the majority of those with B12 deficiency eat plentiful amounts of the vitamin; they simply are unable to absorb or effectively use the vitamin. Some people may even need a greater amount of B12 than the recommended daily allowance.

B12's Many Functions

Vitamin B12 is essential for the proper functioning of many different organ systems in our body. For example, B12 helps in the production of the soft, fatty material called myelin that surrounds and protects nerve fibers. A deficiency in B12 can compromise the myelin and can result in serious neurological problems. Vitamin B12 deficiencies have, in some cases, been misdiagnosed as multiple sclerosis.

Vitamin B12 also plays a critical role in the production of white blood cells, which are key components in our immune system. B12 deficiency has been shown to lead to reduced numbers of white blood cells, and can lead to an increased susceptibility to infections and diseases.

Red blood cells have the important job of carrying oxygen from our lungs to our brain and other organs and tissues. If our body does not get an adequate supply of B12, the red blood cells it produces become abnormally large and are destroyed more rapidly. Fewer functioning red blood cells are then available to circulate throughout the body and carry oxygen. This condition, called anemia, causes the body to feel exhausted and weak.

Vitamin B12—along with vitamin B6, folic acid, and other nutrients—are involved in the process of methylation whereby small parts of molecules, called methyl groups, are transferred to other molecules such as hormones, proteins and DNA. The liver uses methylation to detoxify substances. If there are not enough nutrients to supply an adequate number of methyl groups, levels of homocysteine (an amino acid in the body) increase in our blood and urine. Elevated homocysteine levels have been associated with an increased risk for heart disease.

Methylation is also an important pathway in the removal of estrogens from the body. Failure to provide enough methyl groups allows estrogens to accumulate, and this may lead to a loss of hormone balance in the body.

Because this type of methylation activity can be measured by a laboratory, practitioners can evaluate how well the methylation process is going for their individual patients.

It may come as no surprise that, given the many roles vitamin B12 plays in our overall health, a wide range of medical conditions and disorders have been found to be associated with a deficiency in B12. From conditions that affect women such as infertility and postpartum depression, to those more widespread in the general population such as dementia and immune system disorders, vitamin B12 deficiency may turn out to be a culprit.

B12 and Breast Cancer

DNA, which contains all the genetic instructions for each cell, is continually being damaged, and therefore needs to be constantly repaired. Because methylation controls
both the production and repair of DNA, nutrients that provide methyl groups are linked to the cancer process. In one study investigating the connection between B12 and breast cancer, lead author Dr. Martin Lajous hypothesizes that a high intake of folate, vitamin B6, and vitamin B12 may lower the risk of breast cancer.

Conversely, low levels of folic acid, vitamin B6 and vitamin B12 are associated with an increased breast cancer risk.

B12 and Osteoporosis

Several large studies have demonstrated a strong link between low levels of vitamin B12 and osteoporosis, characterized by thinning, weakened bones. Some studies examined levels of homocysteine, which increases with low B12, and the likelihood of bone fractures. In both men and women, those with the highest concentration of homocysteine were much more likely to fracture a hip or experience a broken bone.

These studies all suggest that vitamin B12 may benefit bone health, while low levels of B12 can lead to the development of osteoporosis.

Ms. Pacholok and Dr. Stuart go on to state that these findings are not surprising as vitamin B12 is crucial to the function of osteoblasts (bone-forming cells). Insufficient levels of B12 may result in decreased amounts of bone-forming cells and thus compromise the strength and durability of bones.

B12 and Infertility

While there are many different causes of female and male infertility, B12 deficiency is one factor that is often overlooked. In some case reports, doctors have reported that anovulation (a failure to release an egg during the monthly cycle) occurs in some women with B12 deficiency due to pernicious anemia.

In these cases, a cause of the B12 deficiency is the decreased production of a particular protein, normally made in the stomach, which is necessary for proper absorption of B12. This leads to the development of malformed red blood cells, known as pernicious anemia.

Some studies have noted a link between B12 deficiency and abnormal estrogen levels that may interfere with implantation of the fertilized egg. Dr. Michael Bennett describes a connection with B12 deficiency with not only a failure to get pregnant but also a failure to successfully carry a baby full-term.

B12 deficiency has also been associated with abnormalities of the cells of the reproductive tract which may extend to the lining of the uterus and cervix and may be diagnosed as cervical dysplasia. Observation of these abnormalities caused by a B12 deficiency can also be mistaken for a precancerous condition.

B12 and Postpartum Depression

Many hormones, amino acids, and nutrients have been shown to play an important role in regulating our moods.

As previously discussed, a deficiency in B12 can attack the nerves in our body stripping them of their myelin coating and disrupting communication between cells in the brain and other parts of the nervous system. Because a B12 depletion affects nerve cells in our brains that control how we feel, think and behave, it is not surprising that a B12 deficiency has been linked to depression.

One kind of mental disorder characterized by depression is postpartum depression. Ms. Pacholok and Dr. Stuart note that "Pregnancy can drastically worsen a pre-existing B12 deficiency because B12 is transferred to the growing fetus throughout pregnancy."

B12 and Dementia

B12 deficiency may seriously impair proper functioning of the nervous system. This deficiency has been shown to affect an individual's mental state, and it can lead to memory loss, fuzzy thinking, personality changes, and erratic moods. These features all appear as classic dementia.

With the growing recognition of the association between B12 deficiency and dementia and other mental illnesses, more attention is being focused on the link between vitamin B12 and Alzheimer's disease.

In a 2006 paper, Joseph G. Hattersley, MA, proposes that an early launch of high dose vitamin B12 treatment soon after the first warning symptoms appear may even turn off the process. Dr. John V. Dommisse states that "most cases of Alzheimer's dementia are actually missed B12 deficiency cases." He believes that approximately 75 percent
of the dementia cases brought on by B12 deficiency could be reversed if the condition is discovered early enough.

B12 and Other Mental Illnesses

As discussed earlier, B12 is important to the health of the nerve cells in our brains that control our moods and behaviors. For that reason, a B12 deficiency can contribute
to severe mental illness including depression, paranoia, and symptoms resembling schizophrenia.

While B12 deficiency is not the cause of most cases of mental illness, it is believed to play some role, particularly in cases involving depression or bipolar disorder.

Testing for B12 Levels

If you believe that you may have a vitamin B12 deficiency, or any of the related health concerns described above, a health care professional can administer a test to measure your B12 levels.

The most common B12 test is a serum test that measures the level of vitamin B12 in your blood serum. Ms. Pacholok and Dr. Stuart say that experts advise further testing if your level is below 350 picograms/milliliter (pg/ml).

A more sensitive and specific test for B12 levels is called the MMA or methylmalonic acid test. This test measures the level of MMA in either urine or blood. The principle behind this test is that vitamin B12 is required to metabolize MMA; in short, an elevated level of MMA indicates decreased B12 activity.

Another way to determine if you are deficient in B12 is to test your homocysteine (Hcy) level. Elevated levels of homocysteine in the blood indicate B12 deficiency, and possible deficiencies in vitamin B6 or folate as well. While this test is not necessary to diagnose B12 deficiency, it is considered a valuable tool along with either a serum B12 or MMA test.

B12 Supplements

Supplemental vitamin B12 is available in three forms: cyanocobalamin, methylcobalamin, and hydroxocobalamin.

While there is some controversy over which form is most preferred, or considered to be most effective, current evidence suggests that methylcobalamin may be superior to the others – especially in cases involving neurological disease.

According to Ms. Pacholok and Dr. Stuart, methylcobalamin is believed to be more effective because it is able to cross the blood brain barrier, thereby leaving the
bloodstream and actually entering into the brain tissue where it is needed. B12 can be supplemented orally, nasally, dissolved under the tongue, or by injection.

Conclusion

After reading about the many critical functions carried out by vitamin B12 in our body – from our bone and blood cells to our reproductive and nervous systems – it is no wonder that B12 is so fundamental to our wellbeing.

Greater recognition of the many health problems associated with B12 deficiency is leading to more testing and diagnosis. And, with supplements now readily available,
more people may be able to address some of their medical concerns. An understanding of the B12 connection to our health continues to increase and shows promise
in one day becoming a routine part of our typical practices for a healthy lifestyle.

References

• Methyl Magic by Craig Cooney, PhD; Andrews McMeel Publishing; Kansas City, MO; 1999.
• Could It Be B12? by Sally M. Pacholok, RN, and Jeffrey J. Stuart, DO; Quill Driver Books, Sanger, CA; 2005.
• "Folate, Vitamin B6, and Vitamin B12 Intake and the Risk of Breast Cancer Among Mexican Women" by Martin Lajous et al.; Cancer Epidemiol Biomarkers Prev, 2006.
• "Low serum vitamin B12 levels are associated with increased hip bone loss in older women: A prospective study" by K.L. Stone et al.; Journal of Clinical Endocrinology &
  Metabolism, 2004.
• "Homocysteine levels and the risk of osteoporotic fracture" by J.B.J. van Meurs, PhD, et al.; New England Journal of Medicine, 2004.
• "Vitamin B12 Deficiency, Infertility and Recurrent Fetal Loss" by Michael Bennett, MD; Journal of Reproductive Medicine, 2001.
• "High-Dose Vitamin B12 for At Home Prevention and Reversal of Alzheimer's Disease and Other Diseases" by Joseph G. Hattersley, MA; Townsend Letter, 2006.
• "Subtle vitamin B12 deficiency and psychiatry: A largely unnoticed but devastating relationship?" by John V. Dommisse, MD; Medical Hypotheses, 1991.