Doctors may recommend vitamin B12 supplements if you have certain health conditions or dietary restrictions. The dosage can vary based on factors such as age, sex, and medical history.
Vitamin B12 is a water-soluble nutrient that’s required for many crucial processes in your body, such as healthy red blood cells.
The ideal dosage of vitamin B12 varies based on your sex, age, and reasons for taking it.
Learn more about the uses of vitamin B12 supplements and the evidence behind the recommended dosages for different people.
Vitamin B12 is an essential nutrient that plays a critical role in several of your body’s processes.
It’s
Vitamin B12 also plays a key role in reducing levels of an amino acid called homocysteine, high levels of which have been linked to chronic conditions like heart disease, stroke, and Alzheimer’s.
Additionally, vitamin B12 is important for energy production. However, there’s currently no evidence that taking B12 supplements increases energy levels in people who are not deficient in this nutrient.
Vitamin B12 is found mostly in animal products, including meats, seafood, dairy products, and eggs. It’s also added to some processed foods, such as cereal and nondairy milk.
Because your body can store B12 for 2 to 5 years, a serious B12 deficiency is rare.
It can be caused by not getting enough of this vitamin through your diet, problems with absorbing it, or taking a medication that interferes with its absorption.
Your doctor may determine if you have a deficiency based on your medical history, lab work and signs or symptoms. Some of the symptoms of low vitamin B12 can include fatigue, headaches, and burning or pins-and-needles sensation of the hands or feet.
If you’re at risk of deficiency or have a known deficiency, taking a supplement may help you meet your needs.
The recommended dietary allowance (RDA) for vitamin B12 for people
Note that the percent of vitamin B12 your body can absorb from supplements is not very high — it’s estimated that your body only absorbs 10 mcg of a 500 mcg B12 supplement.
Here are some recommendations for B12 dosages depending on your circumstances.
Adults under age 50
B12 supplementation is not recommended for healthy people in this age group, since you’ll likely obtain 2.4 mcg from your diet.
For example, if you ate the following, you would consume more than double your daily B12 needs:
However, if you have any issues that interfere with vitamin B12 intake or absorption, you may want to consider taking a supplement.
Adults over age 50
Older adults are more prone to vitamin B12 deficiency.
As you age, your body naturally makes less stomach acid and intrinsic factor.
Stomach acid is necessary to release vitamin B12 from food, and intrinsic factor is required for its absorption.
Due to the increased risk of low absorption, it is recommended that adults
When pregnant
If you are pregnant, you will require slightly higher vitamin B12 than the general population.
Low maternal levels of this vitamin have been
Therefore, the RDA for vitamin B12 during pregnancy is 2.6 mcg. This level can be met through diet alone or with a prenatal vitamin.
When breastfeeding
Vitamin B12 deficiency in nursing infants has been linked to developmental delay.
Additionally, B12 deficiency in infants can lead to lethargy, decreased appetite, and failure to thrive.
Because of this, the RDA when breastfeeding is higher than for pregnancy. The RDA if you’re breastfeeding is 2.8 mcg.
Vegetarians and vegans
Vitamin B12 recommendations do not differ for people following a plant-based diet.
However, the RDA of 2.4 mcg for people under 50 years of age is much harder to meet on a vegetarian or vegan diet.
There are currently no government recommendations for B12 supplement dosages for vegetarians.
However, a healthcare professional can help you determine if you have or are at risk of a B12 deficiency and develop a tailored diet plan to meet your nutritional needs.
Vitamin B12 is a water-soluble vitamin, meaning that your body excretes what you don’t need in your urine, including any excess consumed via supplements or food.
Because it’s relatively safe,
However, vitamin B12 has been shown to cause rare side effects in some cases. For example, vitamin B12 injections may lead to skin changes, such as acne and dermatitis (rash).
People with kidney disease should also avoid high doses of B vitamins unless recommended by a doctor.
Vitamin B12 is a nutrient that plays many essential roles in your body.
The RDA for vitamin B12 ranges from 2.4 mcg for adults to 2.8 mcg during breastfeeding.
Most people meet these needs through diet alone, but older adults, people on strict plant-based diets, and those with digestive disorders may benefit from supplements, though dosages vary based on individual needs.
People with kidney disease should avoid high doses of B vitamins.