Vitamin B12 Deficiency
Vitamin B12 deficiency is a condition in which the body does not receive, or cannot absorb and assimilate, adequate levels of vitamin B12. Vitamin B12 is one of eight B vitamins and has many important functions within the body. All B vitamins, including B12, help the body utilize fats, proteins and carbohydrates for energy. They are essential for healthy hair, eye, skin, liver, and nervous system function. Vitamin B12, in particular, is especially necessary in producing cellular genetic material (DNA and RNA) and normal functioning of nerve cells. B12 works with other B vitamins to create red blood cells, use iron for efficient oxygen transportation, and to regulate the immune system and mood. It also is essential for cellular enzymatic activity that controls inflammatory markers associated with cardiac disease.
Because vitamin B12 is necessary for energy production and in proper functioning of multiple body systems, deficiency can cause a wide range of symptoms. These symptoms may include fatigue, weakness, shortness of breath, heart palpitations, diarrhea, constipation, and pale, sore tongue. If the nerves become involved symptoms may include numbness, or tingling sensation in the fingers and toes. Severe deficiency of B12 can cause nerve damage, vision loss, depression and behavioral changes. Patients with B12 deficiency due to chronic gastritis (see below) may also exhibit hyperpigmentation of the hands.
Causes of Vitamin B12 Deficiency
Vegans and vegetarians may become deficient in B12. Vitamin B12 is a water soluble vitamin that cannot be made by the body. It must be consumed, and is most abundant and accessible in animal food sources such as milk, eggs, and meats. Thus, those who do not consume animal products may become deficient in B12.
Decreased levels of stomach acids may result in inadequate B12 absorption. Vitamin B12 must be released from its protein bonds in the stomach. This occurs when protein is digested by stomach (hydrochloric) acid. If one does not produce enough stomach acid, they may not be able to break down and use the B12 stored in proteins they consume. This can occur due to the use of medications that reduce stomach acid production (for example, to treat GERD or heartburn), such as proton pump inhibitors. Metabolic disorders that affect stomach acid or motility, such as thyroid disease or diabetes, may contribute to B12 deficiency.
Lack of intrinsic factor, a protein secreted by stomach cells which helps absorb B12, will also lead to deficiency. This can occur due to chronic gastritis, in which the lining of the stomach becomes compromised and ceases to function normally. It can also be due to autoimmune processes that attack the intrinsic factor protein or the cells that produce it, leading to their destruction. Reduction of intrinsic factor and B12 deficiency may also be due to infection with H. pylori, the bacteria that can cause stomach ulcers. Lack of intrinsic factor leads to a specific form of deficiency called Pernicious Anemia.
Metformin, a drug used to control blood sugar levels in diabetics, is also associated with vitamin B12 deficiency. The suggested mechanisms by which this occurs include the effect metformin has on the motility of the small intestines, which contributes to overgrowth of bacteria which compete within the intestine for consumption of B12. Additionally in may interfere with intrinsic factor (as discussed above).
Additionally, if absorption of nutrients (due to diseases such as irritable bowel syndrome, Crohn’s disease, pancreatic disease, alcoholism, stomach bypass surgery, celiac disease) is compromised, the intestines may not be able to absorb consumed vitamin B12. Sometimes tapeworm consumed from ingesting contaminated fish can interfere with vitamin B12 absorption. Small intestinal bacterial overgrowth, a condition which can be caused by a variety of factors, can cause B12 deficiency as well through competitive uptake of B12 by intestinal bacteria.
Genetic conditions can also cause vitamin B12 deficiency.
If You’ve Been Diagnosed with Vitamin B12 Deficiency:
A physician may discover vitamin B12 deficiency through particular blood tests. Because B12 deficiency can contribute to elevations of homocysteine and/or methylmalonic acid, these levels may also be tested in the determination of B12 deficiency. Sometimes blood tests will be ordered to detect antibodies against intrinsic factor. A Schilling test may be ordered to further determine the cause of B12 deficiency.
If B12 deficiency is found, the treatment goal is to restore the body’s supply and store of this vitamin. Additionally, contributing factors must be determined. Determining the cause of deficiency (for example, diet, gastritis, medication use, or malabsorption) will be important in determining how to best treat the deficiency and potentially correct the cause. Deficiency due to dietary intake may be reversed through supplementation and dietary amendment. If due to bacterial overgrowth, the antibiotic tetracycline may be administered. In rare and severe cases, blood transfusions may be given. If gastritis or intestinal malabsorption is thought to contribute to deficiency, referral to a specialist to diagnose these disease processes may be initiated.
Supplementation can be accomplished through multiple routes: oral, injection, sublingual, and nasal inhalation. The route of supplementation will be determined in part upon the underlying pathophysiology contributing to the deficiency. For example, oral supplementation may be contraindicated for those with a lack of stomach acid or intrinsic factor. In this case B12 injections can be used.
Sources of vitamin B12 mostly include animal products: milk and milk products, lean meats, chicken, turkey, fish, red meats, and eggs. The B12 in these products is bound to the protein, and must be adequately digested with the help of stomach acid in order for it to be utilized by the body. For those who don’t eat meat products, many fortified cereals include vitamin B12, as do some milk and meat alternatives, and some yeasts.
A Whole Health Perspective
Looking at Vitamin B12 Deficiency through a Whole Health model, we explore the individual’s unique presentation from the 5 Aspects of Whole Health™ perspective.
1. Physically – Risk factors for Vitamin B12 deficiency may include advanced age, those with malabsorption diseases such as inflammatory bowel disease or who have had surgery to the stomach, pancreatic insufficiency (this changes the enzymes necessary to break down and absorb sources of vitamins), certain autoimmune diseases, certain genetic factors, alcohol abuse, pernicious anemia, and SIBO. There is some evidence that Vitamin B12 deficiency correlates with heart disease because of its interaction with homocysteine and methylmonic acid. Over use of medications or supplements to treat stomach acid imbalance or GERD may result in deficiency. Use of birth control pills can also lead to deficiency. Unmanaged chronic stress may contribute to vitamin deficiency by altering stomach acid secretion and absorption and assimilation of vitamins. Additionally, chronic stress may negatively impact immune health and thus increase symptoms in those with deficiency related to immune factors. During prolonged stress, the body needs more vitamin b12 (among others), so being aware of proper diet and supplementation during times of stress or sleep cycle alteration may be important in recovery. Vitamin B12 deficiency is an important factor to be aware of in pregnant and lactating women.
2. Chemically/Nutritionally – Foods high in Vitamin B12 include mostly include animal products: milk and milk products, lean meats, chicken, turkey, fish, red meats, and eggs. For those who don’t eat meat products, many fortified cereals include vitamin B12, as do some milk and meat alternatives, and some yeasts. Vegans and vegetarians may consider appropriate testing and supplementation. Overconsumption of alcohol and/or poor quality food choices may lead to under consumption or malabsorption of vitamin rich foods. When choosing food sources high in Vitamin B12, choosing foods that are organic and/or minimally processed offers the body improved opportunity for health and healing, rather than increased levels of toxins which may impact health negatively. In those with B12 deficiency, a high quality diet low in saturated fats, sugars, refined carbohydrates, additives, alcohol, etc., will support vulnerable physiological systems such as the gastrointestinal, immunological, and nervous systems. Though a quality whole food diet is in general a superior method of vitamin ingestion, oral supplementation can be guided by a health care professional. Vitamin deficiency places stress upon the body, during these times it is important to consume adequate levels of not just vitamin B12, but all the B vitamins, vitamin C, vitamin E, cholesterol, protein, essential fatty acids, and minerals. These nutrients will support the adrenal glands, the glands responsible for proper response and recovery to stress, which in turn will assist in the functioning of all body systems.
3. Emotionally – Potential feelings such as anxiety, depression, anger, and/or frustration, as well as chronic psychological stress, can negatively affect gastrointestinal function and immune function. If deficiency is related to imbalance in these body systems, choosing activities which control stress may potentially positively impact symptoms and development of deficiency. If chronic stress impacts dietary choices or intake, it also may impact Vitamin B12 levels (ie. emotional eating). Some stress relief choices include yoga, meditation, prayer, seeking support of others, or finding a mental health professional to consult with. Vitamin B12 deficiency is also correlated with symptoms of depression, in this situation testing and supplementation should be guided by a health professional.
4. Environmental – Environmental factors which may affect how one consumes sources of Vitamin B12 include familial/social use of food (ie. vegetarian/vegan households, economic factors, traditional/cultural use of foods). Stressful environments (difficult relationships, exposure to air, water, soil toxins, bright lights, loud noises, etc.) increase the overall stress load, which can change food choice, intake, digestion, and gastrointestinal and immune functioning (all factors which may affect Vitamin B12 levels). Some research suggests that reducing overall stress exposure can positively change dietary choices and overall health. Changes in activity levels and exercise may change dietary/vitamin needs, in which case supplementation and intake may need to be modified.
5. Beliefs, Values and Worldview – also identified as Spirituality – Spiritual and/or religious traditions may impact food choice. If these traditions require dietary limitations which decrease Vitamin B12 intake, supplementation may need to be considered. Our relationship with others, our role in our world and the value we place upon this, and our relationship with and value we place upon ourselves can impact how we nourish ourselves with food. Alexandra Shields, Harvard Medical School associate professor of medicine and director of the Harvard-MGH Center on Genomics, Vulnerable Populations and Health Disparities, reports that spiritual/religious experiences have the potential to positively impact overall health. Those with Vitamin B12 deficiency related to disease processes such as GERD, immune imbalance, or pancreatic insufficiency may benefit from regular spiritual practices such as prayer, meditation, or yoga.