Vitamin B12 (cobalamin) is an essential vitamin that is used as a cofactor for enzymatic reactions throughout the body. Supplementation with vitamin B12 can have many positive health benefits.
Why is Vitamin B12 Important?
B12 is involved in healthy cellular metabolism, neurological function, red blood cell production and DNA synthesis. This essential vitamin is also a cofactor in the reaction that transforms homocysteine to methionine. High homocysteine levels are a risk factor for cardiovascular disease, including coronary artery disease and stroke. Adequate consumption and absorption of B12 is essential for preventing fatigue, depression, cardiovascular disease, nerve damage, and maintaining memory and focus. B12 is primarily obtained from animal products including meat, poultry, fish, eggs and dairy.
Frank B12 deficiency is rare, and typically manifests with neurological complications. However, subclinical B12 deficiency is much more common and affects up to 26% of the population. This means that lab values for B12 may be within “normal” range, but the patient is still experiencing subtle symptoms. The elderly are at particular risk for B12 deficiency due to inadequate protein intake, prescription drug use, and malabsorption syndromes. It is estimated that over 20-40% of people over the age of 60 are B12 deficient.
Common signs of B12 deficiency include:
- Loss of appetite
- Memory impairment
- Reduced focus or concentration
- Soreness of the mouth or tongue
- Numbness or tingling in the hands or feet
Causes of Deficiency
There are several causes of vitamin B12 deficiency. One major cause is an autoimmune disease known as pernicious anemia. An often overlooked cause of deficiency are chronic digestive issues and malabsorption. Oral absorption of B12 first requires healthy stomach acid. Low stomach acid increases the risk for H. pylori infections, stomach ulcers, chronic gastritis, bacterial overgrowth and other issues.
- Low intake (vegetarian/vegan diet, alcoholism, elderly)
- Autoimmune (Pernicious anemia)
- Malabsorption due to chronic gastrointestinal issues
- H. pylori infection
- Chronic gastritis
- Small intestinal bacterial overgrowth (SIBO)
- Crohn’s disease
- Celiac disease
- Low stomach acid
- Surgery (post-gastrectomy and ileal resection)
- Hormonal (oral contraception, hormone replacement therapy)
- Pharmaceuticals (metformin, proton pump inhibitors, histamine H2-receptor blockers)
- Pregnancy and lactation
Forms of B12
Cyanocobalamin: this is the most common form of B12 used in oral supplements and injections. It is also the most inexpensive and readily available for consumers. Approximately 25% of people will respond positively to this form of B12. This form does contain a small amount of cyanide and requires extra processing by the body to transform it into a cofactor ready for use.
Hydroxocobalamin: This form of B12 is slightly longer acting, and a good option for those who wish to avoid cyanocobalamin. Like cyanocobalamin, it requires extra steps to be transformed into the active coenzyme. Hydroxocobalamin is usually only available in injectable and oral forms from compounding pharmacies. Additionally, it is the most common form of B12 found in food.
Methylcobalamin: This is the active form of B12 that is most bio-available and requires little processing. Because methylcobalamin must be obtained from a compounding pharmacy, these formulas typically contain fewer preservatives and contaminants. This is the form I typically use with my patients.
Adenosylcobalamin: This is the other active form of vitamin B12, and acts as a coenzyme in some B12-dependent reactions. Adenosylcobalamin is only found in oral forms. It is required by those who are sensitive to methylated B vitamins.
Injected Vs. Oral?
There is ongoing debate over the efficacy of oral vs. injected B12. Some research indicates oral forms are just as effective as B12 shots. However, many naturopathic physicians would argue there is enormous clinical benefit the injected form. Many people report immediate benefit, such as increased energy and better mood, within hours of their B12 shot. Additionally, any issues with digestion or absorption may make you a candidate for B12 injections. An alternative healthcare practitioner can help you determine which form and source is best for your unique needs.
Potential Benefits of Intramuscular (injected B12)
In a clinical setting, many physicians observe their patients having superior results when receiving injected B12 vs. oral forms.
- Increased energy levels
- Elevated mood
- Improved sleep
- Improved focus, memory and concentration
- Heart disease prevention
- Reduced joint pain
- Reduced PMS symptoms
Vitamin B12 supplementation can be beneficial for a variety of conditions and symptoms. Specific populations, such as the elderly, vegetarians, and those with chronic digestive issues are at greater risk of deficiency. Talk to your naturopathic physician to help determine if B12 supplementation is right for you.
Dr. Natalie Walch is a licensed naturopathic physician practicing in Kent, WA. Her clinical focus includes chronic gastrointestinal conditions, autoimmunity and chronic disease. She is currently accepting new patients. Call to schedule today!
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