Vitamin B12 does a lot of things for your body. It helps make your DNA and your red blood cells. Since your body doesn't make vitamin B12, you have to get it from animal-based foods or from supplements. And you should do that on a regular basis, because your body doesn’t store vitamin B12 for a long time.
How Much to Get?
The answer depends on things including your age, your eating habits and medical conditions, and what medications you take.
The average recommended amounts, measured in micrograms (mcg), vary by age:
Infants up to age 6 months: 0.4 mcg
Babies age 7-12 months: 0.5 mcg
Children age 1-3 years: 0.9 mcg
Kids age 4-8 years: 1.2 mcg
Children age 9-13 years: 1.8 mcg
Teens age 14-18: 2.4 mcg (2.6 mcg per day if pregnant and 2.8 mcg per day if breastfeeding)
Adults: 2.4 mcg (2.6 mcg per day if pregnant and 2.8 mcg per day if breastfeeding)
Food Sources of Vitamin B12
You can get vitamin B12 in animal foods, which have it naturally, or from items that have been fortified with it.
Animal sources include dairy products, eggs, fish, meat, and poultry. If you’re looking for a food fortified with B12, check the product’s Nutrition Facts label.
You can also get vitamin B12 deficiency if you follow a vegan diet (meaning you don't eat any animal products, including meat, milk, cheese, and eggs) or you are a vegetarian who doesn't eat enough eggs or dairy products to meet your vitamin B12 needs. In both of those cases, you can add fortified foods to your diet or take supplements to meet this need.
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