- What other names is Vitamin B12 known by?
- What is Vitamin B12?
- How does Vitamin B12 work?
- Are there safety concerns?
- Are there any interactions with medications?
- Dosing considerations for Vitamin B12.
Vitamin B12 is used for treating and preventing vitamin B12 deficiency, a condition in which vitamin B12 levels in the blood are too low. It is also used to treat pernicious anemia, a serious type of anemia that is due to vitamin B12 deficiency and is found mostly in older people. For this purpose, people use either a supplement that is taken by mouth or a gel that is applied inside the nose.
Vitamin B12 is also used for memory loss; Alzheimer's disease; boosting mood, energy, concentration and the immune system; and slowing aging. It is also used for heart disease, lowering high homocysteine levels (which may contribute to heart disease), male infertility, diabetes, sleep disorders, depression, mental disorders, weak bones (osteoporosis), swollen tendons, AIDS, inflammatory bowel disease, asthma, allergies, a skin disease called vitiligo, preventing cervical and other cancers, and skin infections.
Some people use vitamin B12 for amyotrophic lateral sclerosis (Lou Gehrig's disease), multiple sclerosis, preventing the eye disease age-related macular degeneration (AMD), Lyme disease and gum disease. It is also used for ringing in the ears, bleeding, liver and kidney disease, and for protection against the poisons and allergens in tobacco smoke.
Vitamin B12 is applied to the skin either alone or in combination with avocado oil for psoriasis and eczema.
Vitamin B12 is frequently used in combination with other B vitamins in various vitamin B complex products.
- Inherited Vitamin B12 deficiency (Imerslund-Grasbeck disease). Injecting vitamin B12 as a shot for 10 days followed by monthly injections for the remainder of life is effective for treating people with an inherited disease that results in poor absorption of vitamin B12.
- Pernicious anemia. Injecting vitamin B12 as a shot, as well as taking through the nose or by mouth, is effective for treating low red blood cell counts caused by poor absorption of vitamin B12.
- Vitamin B12 deficiency. Taking vitamin B12 by mouth, through the nose, or as a shot is effective for treating vitamin B12 deficiency.
Likely Effective for...
- Cyanide poisoning. Administering hydroxocobalamin (Cyanokit), a natural form of vitamin B12, as a shot for a total dose of up to 10 grams is likely an effective treatment for cyanide poisoning. Treatment of cyanide poising with hydroxocobalamin (Cyanokit) has been approved by the U.S. Food and Drug Administration (FDA).
- High level of homocysteine in the blood (Hyperhomocysteinemia). Taking vitamin B12 by mouth, along with folic acid and sometimes pyridoxine (vitamin B6), can lower blood levels of homocysteine.
Possibly Effective for...
- An eye disease called age-related macular degeneration (AMD). Some research shows that taking vitamin B12 with other vitamins, including folic acid and vitamin B6, might help prevent an eye disease called age-related macular degeneration.
Possibly Ineffective for...
- Sleep disorders. Taking vitamin B12 by mouth does not seem to help people with sleep disorders.
- Mental function. Taking vitamin B12, alone or in combination with folic acid and vitamin B6, does not seem to improve memory, language, or the ability to organize and plan in elderly people.
- Stroke. Research suggests that people who consume more vitamin B12 in their diet or those who take vitamin B12 supplements do not have a reduced risk of stroke or stroke reoccurrence.
Insufficient Evidence to Rate Effectiveness for...
- Alzheimer's disease. Early research suggests that higher vitamin B12 intake does not seem to prevent Alzheimer's disease.
- Preventing re-blockage of blood vessels after heart artery dilation (balloon angioplasty). Research is inconsistent about the benefits of taking folic acid plus vitamin B6 and vitamin B12 following angioplasty. Some research suggests that it might decrease the risk of re-blockage of the blood vessels after balloon angioplasty. However, it does not seem to benefit people who had a tube (coronary stent) placed in the arteries.
- Eczema (atopic dermatitis). Early research shows that applying a vitamin B12 cream (Regividerm) to the affected area twice daily helps treat eczema.
- Breast cancer. There is no evidence that dietary vitamin B12 alone reduces the risk of breast cancer. However, vitamin B12 may reduce the risk of breast cancer when taken with folate, vitamin B6, and methionine.
- Canker sores. Early research shows that taking vitamin B12 1000 mcg under the tongue (sublingually) might help reduce the number of canker sore outbreaks, the duration of outbreaks, and pain caused by the canker sores.
- Cervical cancer. Early research suggests that different forms of vitamin B12 taken together with a thiamine derivative (benfotiamine) and vitamin B6 might improve some symptoms of nerve pain associated with diabetes.
- Nerve damage caused by diabetes. Early research suggests that different forms of vitamin B12 taken together with a thiamine derivative (benfotiamine) and vitamin B6 might improve some symptoms of nerve pain associated with diabetes.
- Fatigue. There is some evidence that receiving shots containing 5 mg of vitamin B12 twice weekly might improve general well-being and happiness in people with fatigue.
- High triglyceride levels. Some evidence suggest that taking 7.5 mcg of vitamin B12 together with 5 grams of fish oil might be more effective then fish oil alone when used daily to reduce total cholesterol and triglyceride levels.
- Lung cancer. Early evidence suggests that there is no relationship between levels of vitamin B12 in the blood and the risk of lung cancer.
- Psoriasis. Early research shows that a specific cream containing vitamin B12 and avocado oil (Regividerm, Regeneratio Pharma AG) reduces symptoms of psoriasis as effectively as standard care and causes less irritation.
- Shaky-leg syndrome. There are some reports that one form of vitamin B12 (cyanocobalamin) can help reduce tremors due to shaky-leg syndrome.
- Chronic fatigue syndrome (CFS).
- Heart disease.
- Lyme disease.
- Immune system problems.
- Memory problems.
- Multiple sclerosis.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
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