Vitamin B12 deficiency can cause long term nerve degeneration

Vitamin B12 (Cobalamin):

Neurological symptoms of B12 deficiency may include:

  • numbness and tingling of the arms and legs; problems walking; disorientation; memory loss; mood changes that may resemble schizophrenia; and dementia.  Damage may occur to the myelin sheath which surrounds and insulates nerves like the plastic coating around an extension cord.  Nerve damage and mental health symptoms may become permanent with long term deficiency of vitamin B12.

Digestive symptoms may include:

  • loss of appetite, a painful tongue, and constipation.  The reason for there to be digestive symptoms associated with B12 deficiency is not well understood.  One theory suggests that undiagnosed digestive problems might have been an initial cause of the  B12 deficiency.

Symptoms of vitamin B12 deficiency may also include:

  • pernicious anemia and megaloblastic anemia which are hemoglobin deficiencies that have symptoms of tiredness.  Folate deficiency symptoms are also possible because B12 is necessary in folate metabolism.  Increased heart disease risk from elevated homocysteine levels may result from B6,  B12, or folate deficiency.

People who may be more at risk for vitamin B12 deficiency include:

Those with malabsorption problems, or people with chronic use of antacids and those who are over age 60.  A specific protein cofactor called the intrinsic factor and normal stomach acidity levels are necessary for B12 absorption to be able to occur.  Some individuals receive monthly injections of B12 after reaching older age and some people need to receive them monthly throughout life due to having chronically low vitamin B12 for other reasons than normal aging such as a genetic issue with their production of the intrinsic factor protein.

Sublingual tablets of the supplement are also available which are absorbed in the mouth, bypassing any problems with the rest of the digestive system.

A genetic difference may exist that causes some individuals to require the methylated active form of B12 rather than being able to benefit from the more commonly available supplement which is an unmethylated and therefore inactive form.  [More about methylcobalamin.] A genetic screening test would need to be ordered to find out if there were any differences in the gene that might cause an inability to methylate vitamin B12 or folate/(folic acid is the commonly used supplement which is also in the unmethylated form, and therefore inactive for someone with a genetic inability to perform the methylation reaction – meaning an enzyme is malfunctioning somewhere in the complex chemical chain of events.)

A problem with lower digestive acidity in the stomach could also be managed simply by adding a side dish or condiment to meals that contains vinegar or acidic ingredients. Examples from around the world include chutneys, pickles, lime or lemon juice/fresh wedges, vinegary salad dressing, salsa or Tabasco Sauce, and Worcestershire sauce.

  • What is Worcestershire Sauce? (thespruce) (and how do you spell it?)- It is an interesting story – featuring the chemists Lea and Perrins. (Lea & Perrins is still the best selling brand of Worcestershire Sauce). Who knew chemistry could be so delicious?

Schizophrenia may also be associated with an increased risk for low levels of vitamin B12. Read more: (

Low stomach acid may be an underlying issue with symptoms of schizophrenia and in other mental health disorders. The balance and variety of microbes living within the gastrointestinal tract also may be involved in symptoms resembling mental illness. (Digestion & schizophrenia /PMC4437570/)

Pickles that are made fresh and need to be refrigerated  can be a source of healthy intestinal microbes, in a similar way to the healthy bacteria found in yogurt with active probiotics or Kefir drinks.  A variety of traditional products with live cultures are listed here – and a new one, probiotics are being added to chocolate in some products: ( & chocolate) Scientists studying the microbiome tend to recommend the live culture foods rather than supplements of probiotics – based on my overview impression of multiple sources. An overview regarding the current recommendations about probiotic supplements is available here: (washingtonpost/people-love-probiotics-but-do-they-really-help/2017/05/19)

Probiotics refers to products that contain actual good guy bacteria, while prebiotics refers to foods that contain fiber or other nutrients which the good guy bacteria need to eat in order to survive and flourish – in competition with the more negative strains of bacteria or with yeasts or other microbes which might be found within our gastro-intestinal tract.

Eating vegetables and other foods that are good sources of some types of fiber also helps support healthier intestinal microbes, a few foods that provide the types of fiber that our intestinal microbes need to eat in order to flourish and protect us from more negative types of microbes, are listed here: (

It is a very good idea to get adequate fiber in the daily diet – because starving microbes will start breaking down and consuming edible portions of the intestinal cells for nourishment – if forced, and it may leave the body more at risk for infection ( – but why starve your good guy microbes? Our intestinal microbes may also help prevent anxiety. (

Food Sources of Vitamin B12 include: 

  • shellfish, fish, meat, poultry, eggs, milk, cheese, dairy products, Nutritional or Brewer’s yeast.  Vegetarians who don’t eat dairy, eggs, fish or other meat products may need a supplement or nutritional yeast, a vegan food source of vitamin B12. (nutritional yeast/pubmed/11146329)
  • See the post on Vitamin B6 for more information about how the group of B vitamins work together in energy metabolism and cell growth.

Reference for more information:

An Evidence-based Approach to Vitamins and Minerals:  Health Benefits and Intake Recommendations, 2nd Ed., by J. Higdon & V. Drake, (Thieme, Stuttgart / New York, 2012)

  • A description and source for purchasing the text: (
  • A review of the text: (
  • The text is produced in cooperation with the Linus Pauling Institute. He is a researcher who used large doses of vitamin C to cure cancer tumors. His work was met with skepticism. More recently research supports his work in that a specific type of cancer cells is very susceptible to vitamin C – while to the rest of the body it is water soluble and non-toxic at the level that was toxic to the cancer cells. (

Last reviewed and revised on 9/30/2017.

Disclaimer: This information is provided for educational purposes within the guidelines of fair use. While I am a Registered Dietitian this information is not intended to provide individual health guidance. Please see a health professional for individual health care purposes.

The Academy of Nutrition and Dietetics has a service for locating a nutrition counselor near you at the website (

Probiotics, vitamin K and calcification

Vitamin K is made with the help of probiotics and our ‘good guy’ intestinal bacteria.  Adequate vitamin K may help prevent calcification of soft tissue and potentially reduce the risk for heart disease and some types of cancer. Healthy intestinal bacteria can make vitamin K in a form that is well absorbed compared to the form found in vegetables and a few other foods.Vitamin K1 is more common in the diet in many green vegetables but it is poorly absorbed. Vitamin K2 is found in foods made with active bacterial cultures like yogurt, sauerkraut, kim chee and some cheeses.

The richest food sources of vitamin K include green leafy vegetables like spinach, kale, Brussels sprouts and broccoli. It is also found in small amounts in egg yolk, some meats, flatfish and eel. Dairy products like yogurt or cottage cheese may contain vitamin K as a side product of the active cultures. Natto, miso, tempeh, kim chee and other live cultured products may also be a source of vitamin K depending on the type of bacteria used in processing. Sauerkraut and dill pickles sold from a refrigerated case may be a source of the live ‘good guy’ bacteria. The fermented products provide some vitamin K and provide the good guy bacteria that can keep making more vitamin K while protecting against yeast and less friendly bacteria. Spoilage does occur with live products. Food safety guidelines and ‘use by dates’ should be followed. [4] [6]

Probiotic supplements are also available that are designed to provide some of the good guy bacteria in a capsule. Check the source for quality control standards and storage recommendations.

Vitamin K helps the body make the hormone, osteocalcin, which helps signal calcium to enter bone tissue [4] and is important for regulating blood sugar levels.[13] Adequate vitamin K helps the calcium stay in the bone tissue and reduces the risk of soft tissue calcification. Hardening of the breasts may not lead to heart attacks, a risk with arteriosclerosis, or the hardening of arteries from calcium/cholesterol deposits, [910] but the condition isn’t likely to be comfortable either. Calcium is electrically active inside of the cell and can signal membranes to break down. Calcium deposits in soft tissue may be enclosed in fatty cholesterol deposits to help prevent the risk of inflammatory membrane break down.

Vitamin K is essential for blood to clot but it is also very important for preventing calcification of soft tissue. Calcium deposits add to hardening of the arteries or arteriosclerosis but abnormal calcification is also seen in some cases of breast cancer. [3] Calcification of soft tissue becomes more common in people over 50 and is frequently considered a normal part of aging. However soft tissue calcification can be a symptom of excess vitamin D intake and can be a symptom of vitamin K or magnesium deficiencies.

A study found less incidence of prostate and lung cancer in participants who reported more intake of vitamin K foods. The link with breast or colon cancer was less clear but the study was based on self reported intake of common foods and cheese was the richest food source of vitamin K reported (cheese is also a source of calcium). None of the study participants had an estimated intake of vitamin K that met the RDA. In the U.S. 120 mcg is recommended for men and 90 mcg for women. In the study 24,340 adults were followed for ten years and averaged less than 100 mcg/day. [7] A cup of carrots has about 15 mcg, a cup of kale has 1054 mcg (but the form is not well absorbed) and a cup of sauerkraut has 81 mcg. [8]

Bacteroides is a family of bacteria that are commonly found in the intestines. Some helpful bacteria are known to make vitamin K. Some of the Bacteoides family are more helpful to health than others. Having a variety of bacteria in the intestines can reduce the growth of other more deadly bacteria and helps prevent excessive yeast growth. Intestinal health is not a pleasant topic but intestinal ill health is even less pleasant.

A study about celiac disease risk tested for types of Bacteroides species in newborns. A difference in intestinal species was noted based on the genetic differences between the infants and whether they were fed with human milk or commercial infant formula. Infants without the high risk genotype and infants receiving human milk feedings had more of the healthier species of Bacteriodes. [1] This suggests that some infants and people may be more at risk than others for intestinal imbalance which can result in poor nutrient absorption and deficiencies. Probiotics from foods or supplements could be helpful as part of the daily diet.

Probiotic supplements can not supply all types of healthy bacteria in a shelf stable form. Freshly prepared fermented foods may be a better source of some types of the healthy bacteria. [12]  Kefir is a type of active culture beverage that is made from milk similar to the way that yogurt is made. Infant formula possibly could be prepared with the healthy Bacteroides species to help establish healthy digestion and vitamin K. Kefir and other active culture products spoil more rapidly so food safety risks would need to be tested with any new products. Infants typically are given supplemental vitamin K at birth because there is little found in the breast milk. The healthy bacteria that are promoted by the human milk feeding could be providing the vitamin K infants need once the good guy bacteria are established in the intestines of the infant. (unpleasant to think about but healthy for digestion and strong bones).

Digestive issues may be helped by vitamin K and probiotic foods or supplements. And having adequate vitamin K can help prevent calcification of the soft tissue and osteoporosis of the bones. While calcification itself is not proven to be a cause of cancer or heart disease, calcium deposits are found in tumors and in arteriosclerotic plaque which suggests that excess calcium is involved.

Disclaimer: Opinions are my own and the information is provided for educational purposes within the guidelines of fair use. While I am a Registered Dietitian this information is not intended to provide individual health guidance. Please see a health professional for individual health care purposes.

Reference List

  1. Sanchez E.,, “Influence of Environmental and Genetic Factors Linked to Celiac Disease Risk on Infant Gut Colonization by Bacteroides Species” Applied and Environmental Microbiology, Aug. 2011, p. 5316–5323 pdf: [] *an increased prevalence of B. vulgatis was found in infants with the HLA-DQ genotype that is associated with increased risk for developing celiac disease. An increased prevalence of B. uniformis was associated with infants without the high risk genotype and with infants who received breast milk feedings.
  2. Itzhak Brook, “Bacteroides Infection,” []
  3. Johnson K., “Breast Calcifications.” (last reviewed Oct. 28, 2012) webmd: []
  4. Vermeer C., “Vitamin K: the effect on health beyond coagulation an overview.” Food & Nutrition Research 2012. 56: 5329 – DOI: 10.3402/fnr.v56i0.5329 pdf, full article: []
  5. Lev M., “Sphingolipid biosynthesis and vitamin K metabolism in Bacteroides melaninogenicus.” Am J Clin Nutr. 1979 Jan;32(1):179-86. Full article [] * This link is really about a different topic. Vitamin K may be important for assembling phospholipids that are used in membranes.
  6. King-Nosseir A., “Eating Well: Bones need more than just calcium,”  (5/16/2012) []
  7. Higher vitamin K intake tied to lower cancer risks.” (March 31, 2010) Reuters: [] *This discusses the results of a large study but the vitamin K intake was based on self reported food intake and cheese was the primary source they mention tracking.
  8. Vitamin K Content of Common Foods.” University Healthcare Thrombosis Service, My Warfarin Therapy, []
  9. Hardening of the Arteries.” (June 3, 2012) pubMed: []
  10. Howenstine J., “Arteriosclerosis Can Be Reversed, Part 1.” (7/24/2008) []
  11. Cuomo M.I., “A World Without Cancer, The making of a new cure and the real promise of prevention.” (2012, Rodale Press, New York) [Amazon] *breast cancer tumors are described as a chalky white that stands out from the surrounding tissue. Diagnostic screening was described that differentiates between abnormal and normal calcification of the breast. ** My position is that calcification of the breast or arteries is abnormal and is related to long term nutrient deficiencies or sometimes parathyroid cancer or other unusual disease rather than being a normal part of aging.
  12. Myhill S., “Probiotics – we should all be taking these all the time and double the dose following antibiotics and gastroenteritis.”  []
  13. Osteocalcin hormone can regulate glucose levels: Research” (July 23, 2010) []