Key Facts
- Vitamin B12 is needed to keep your body’s nerves and blood cells healthy.
- Vitamin B12 is found naturally in some animal products and is added to some plant-based foods too.
- A diet low in vitamin B12 can cause anemia.
Vitamin B12 is needed to keep your blood cells healthy and is used by the body to make proteins like hormones and enzymes needed for digestion. Most people can easily get all the vitamin B12 they need from food. However, some groups of people, such as those who follow a vegan, or mostly plant based diet, might not get enough vitamin B12 from food. Over time, not getting enough vitamin B12 from food can cause anemia, which is a condition that makes it harder for your red blood cells to work well. Without enough vitamin B12, someone may feel tired, weak, or confused and may have low appetite or numbing in their hands and feet.
How much Vitamin B12 do I need every day?
The amount of vitamin B12 you need each day, or recommended daily allowance (RDA), depends on your age. If you are 9 to 13 years old, you need 1.8 micrograms each day. If you are 14 years old or older, you need 2.4 micrograms each day.
What foods are good sources of Vitamin B12?
Vitamin B12 is found naturally in animal products and is also added to certain foods – this is called being “fortified”. You can meet your requirement from eating foods that naturally contain vitamin B12 or are fortified, or by taking a supplement if necessary. Good food sources of vitamin B12 include:
- Fish and seafood
- Meat
- Poultry
- Eggs
- Cheese
- Milk
- Yogurt
- Fortified foods such as cereals, soy milk, and meat substitutes
If you follow a strict vegan diet (do not eat any animal products, including milk and eggs), then you should take a vitamin supplement or eat fortified foods (foods that have vitamin B12 added). Check nutrition facts labels to find products such as breakfast cereals, cereal bars, soymilk, and meat substitutes that are fortified with vitamin B12. Nutritional yeast is a product that some vegans choose to cook with; it is seasoning fortified with vitamin B12 and can be found at some specialty grocery stores or online.
| Food | Serving Size | Micrograms of B12 per Serving |
| Dairy Products | ||
| Cow’s Milk, reduced fat | 1 cup | 1.4 |
| Swiss Cheese | 1 ounce (usually about 1 slice) | 0.9 |
| Ricotta Cheese | 1/2 cup | 1.0 |
| Greek Yogurt, nonfat | 1 container (156 g) | 1.0 |
| Yogurt | 1 cup | 1.4 |
| Meat, Poultry, Fish, Other | ||
| Chicken breast | 3 ounces | 0.2 |
| Hamburger, lean | 3 ounces | 2.2 |
| Shrimp | 3 ounces | 1.4 |
| Sirloin steak | 3 ounces | 1.4 |
| Salmon, Atlantic | 3 ounces | 2.6 |
| Eggs | 1 | 0.6 |
| Tempeh | 1 cup | 0.1 |
| Tuna fish, canned | 3 ounces | 2.5 |
| Fortified Foods | ||
| Cheerios® | 1 cup | 1.9 |
| Special K® | 1 cup | 6.0 |
| Wheaties® | 1 cup | 4.0 |
| Whole Grain Total® | 1 cup | 6.4 |
| Nutritional yeast, fortified | 1/4 cup | 17.6 |
| Plain soy milk | 1 cup | 3.0 |
Our health guides are developed through a systematic, rigorous process to ensure accuracy, reliability, and trustworthiness. Written and reviewed by experienced healthcare clinicians from Boston Children's Hospital, a Harvard Medical School teaching hospital and consistently ranked as a top hospital by Newsweek and U.S. News & World Report, these guides combine clinical expertise, specialized knowledge, and evidence-based medicine. We also incorporate research and best practices from authoritative sources such as the CDC, NIH, PubMed, top medical journals, and UpToDate.com. Clinical specialists and subject matter experts review and edit each guide, reinforcing our commitment to high-quality, factual, scientifically accurate health information for young people.