Medically reviewed on September 9, 2022 by Jillian Foglesong Stabile, MD, FAAFP. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.
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How important is vitamin B12, and how much vitamin B12 should I take? Different bodies need different things—and much like the amounts of food or water you take daily. Your daily dose of vitamin B12 should be tailored to your body’s unique needs. In most cases, dose recommendations are linked to your age and biological sex. 
Do you suffer from extreme tiredness or lack of energy? Feeling faint? Do you have heart palpitations often? In that case, you might have low vitamin B12 levels.  You may be looking to begin a B12 vitamin regime to combat a vitamin B12 deficiency or to fill nutritional gaps in your diet. Whether you’re curious about B12 due to a recent diagnosis or simply want to learn, “How much vitamin B12 should I take?” we’ve compiled this guide with all body types and life circumstances in mind.
The National Institutes of Health (NIH) recommends a daily B12 allowance of 2.4 mcg (micrograms) for the average adult.  However, vitamin B12 intake can be particularly important for children, and intake requirements can be linearly related to age.
Researchers at NIH and experts at Mount Sinai Hospital agree on the following recommendations per age group: 
Young Children (0-4) – Vitamin B12 is just as essential for newborns and toddlers. Experts recommend that children 6 months or younger consume 0.4 mcg a day, increasing to 0.5 mcg a day for 6 months to 1-year-old children, and 0.9 mcg daily for children aged 1 to 3. However, it is generally recommended to consult a healthcare provider before providing children with supplements. Typically, diet can provide sufficient B12 for this age group. 
Kids and teens (4-18) – Research suggests that this age group should expect to increase their vitamin B12 dosage every 3 to 4 years until age 14. The recommendation for ages 4 to 8 is a 1.2 mcg daily dose. Meanwhile, 1.8 mcg is recommended for ages 9 to 13, and once individuals reach the age of 14, the dosage recommendation jumps to the adult standard of 2.4 mcg a day. 
Young adults (19+) – For adult bodies of all genders, 2.4 mcg a day is the recommended dosage. However, your body doesn’t necessarily absorb all the B12 you consume. According to the NIH, you absorb only about 50% of the B12 you take in.  You’ll want to consider your particular routines to determine how best to supplement your diet with B12 or consider having your vitamin B levels tested.
Older adults (50+) – The National Research Center on Nutrition and Aging suggests that older adults do not need more than the suggested amount of 2.4 for younger adults.  However, studies contend that the body’s ability to absorb B12 may decrease with age. If you’re older, you may also want to have your B12 level tested to gain the full picture of the dosage you need.
Adding a vitamin B12 supplement into your routine can be particularly necessary if you have conditions or diet restrictions that limit your B vitamin retention or intake. When it comes to B12 supplementation, pregnant and breastfeeding individuals need more oral vitamin B12. Here are a few common conditions or circumstances that may benefit from higher amounts of B12 supplements: 
If you’re considering an increase in B12, it’s important to note that B12 is a water-soluble, non-toxic compound, which means overdosing is unlikely. The National Resource Center for Nutrition and Aging confirms there is no set “upper-level limit” for vitamin B12 dosage. 
B12 is a key player in your body’s day-to-day performance.  In particular, B12 assists with the development of 3 vital bodily elements:
Essentially, B12 carries two cofactor molecules—compounds that help enzymes perform their functions.  Think of enzymes as construction workers performing labor and cofactors as the tools necessary for the workers to get the job done.
As an essential vitamin, B12 contributes to your overall well-being. In particular, B12 is central to maintaining processes related to blood and the brain. Biological functions that B12 can help support may include: 
As an inherent part of DNA production, B12 can touch every faction of the body’s systems. The vitamin may also be linked to physical benefits, including: 
You can remedy low vitamin B12 with an oral supplement or vitamin B12 shots. What vitamins should I take daily? In addition to vitamin B12, experts also recommend adding vitamin B9 or folic acid. This is to help iron work better.
Ensuring your diet contains all the right nutrients you need can feel like putting together a puzzle—one with many vitamins, minerals, and other key ingredients. When it comes to keeping yourself healthy, B12 is a piece of the nutritional puzzle you don’t want to miss.
With that, Everlywell can help. Our no-stress, once-a-day B12 supplements may be just what your system needs. Capped at 300 mcg, our B12 tablets account for your body’s natural absorption rates.
With your wellness and patterns in mind, Everlywell products are non-GMO and vegan to give those with every kind of diet requirement the option to take control of their health.
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