Vitamin B12 is the common name for a nutrient known scientifically as methylcobalamin.
It's used as a dietary supplement and to treat certain anemias.
Vitamin B12 plays an important role in helping the body make red blood cells.
Vitamin B12 Deficiency
If you have low levels of vitamin B12, you may feel weak, have less energy, and experience slow thinking -- a condition called pernicious anemia.
Other symptoms of pernicious anemia include numbness or tingling in the fingers and toes.
Your doctor will run blood tests to determine if your B12 levels are low.
People who eat a plant-based diet (vegans) are at greater risk because animal products often contain vitamin B12 naturally.
Older people are at higher risk of a vitamin B12 deficiency, too, because your body has a harder time absorbing the vitamin as you age.
Also, low levels of folic acid and low levels of vitamin B12 tend to go hand-in-hand.
Vitamin B12 Warnings
Talk to your doctor before taking vitamin B12 if you:
- Are allergic to vitamin B12 or any other ingredients found in the drug
- Have a genetic condition called optic atrophy where the nerve that connects the eye to the brain wastes away
- Have blood in your urine
- Have an ongoing infection
- Have low iron or folate levels
- Have a bone disease called polycythemia
Pregnancy and Vitamin B12
Depending on its form and the dose, vitamin B12 has two different safety profiles for pregnant women.
Vitamin B12 tablets that you swallow or let melt under your tongue are considered safe during pregnancy.
It's not clear, however, whether high-dose vitamin B12 could harm your unborn baby.
In either case, you should tell your doctor if you are pregnant or plan to become pregnant before taking this medication.
You should also tell your doctor if you are breastfeeding or plan to breastfeed.
Vitamin B12 is found in breast milk and is therefore not recommended for mothers who are breastfeeding.
Vitamin B12 Interactions
It's always important to share with your doctor and pharmacist all of the medications you are taking.
This includes prescription and over-the-counter (OTC) medications, supplements like vitamins and other dietary supplements (Nutritional shakes, protein powders, etc.), herbals, and any illegal and recreational drugs.
Some medications that have serious interactions with Vitamin B12 are:
- Leukeran (chlorambucil)
- Prilosec (omeprazole)
- Colcrys and Mitigare (colchicine)
- The herbal supplement goldenseal
Vitamin B12 and Alcohol
Alcohol actually decreases levels of B vitamins in the body -- especially if you drink a lot.
You should avoid or limit alcohol consumption while taking vitamin B12.
Vitamin B12 and Grapefruit Juice
You should avoid eating grapefruit and drinking grapefruit juice while taking vitamin B12.
Vitamin B12 Dosage
How much vitamin B12 you should take will depend on your age and condition.
Talk to your doctor or pharmacist about the right dose for you, and read the label carefully.
Vitamin B12 Benefits
- Helps Maintain Energy Levels
- Prevents Memory Loss and Lowers Risk of Neurodegenerative Disease
- Boosts Mood and Helps the Nervous System to Properly Function
- Plays a Role in Maintaining Heart Health
- Needed for Healthy Skin and Hair
- Aids in Digestion