Vitamin B12 for vegetarians: how to read your B12 result
Why vegetarians and vegans in India often run low on vitamin B12, what a low normal B12 level means, and the usual reference doses.
By the Beyond Humans team. , 2 min read
About 1 in 2 Indians tested in large studies had low vitamin B12. It is even more common among vegetarians, and nearly universal among vegans who don't supplement. Here's why, and how to read the number on your report.
Why vegetarians run low
Vitamin B12 is made by bacteria, and in our diet it comes almost only from animal foods: milk, curd, paneer, eggs, fish and meat. Plants don't make it. A vegetarian who has dairy every day gets some B12, but often not enough. A vegan diet has none unless foods are fortified.
Other things that lower B12:
- Metformin, the diabetes medicine, taken for a long time.
- Acid reducing medicines (like omeprazole or pantoprazole), because stomach acid helps release B12 from food.
- Age. Absorption drops after 50.
What a low B12 can feel like
Tiredness, pins and needles in hands or feet, a sore tongue, mouth ulcers, low mood and trouble focusing can all come with low B12. None of these is specific to B12, which is why a blood test is the way to know.
Reading your B12 result
B12 is reported in pg/mL in India (pmol/L in some labs; multiply pmol/L by 1.355 to get pg/mL). A common way to read it:
- Under 200 pg/mL: low.
- 200 to 300 pg/mL: low normal. Many labs print this as normal, but people in this zone can still be short of B12, so it is worth acting on.
- 300 to 900 pg/mL: in range.
- Over 900 pg/mL: above range. Usually from supplements or injections. If you take none, mention it to your doctor.
Under 100 pg/mL is very low and worth a doctor's visit soon.
Some labs offer Active B12 (holotranscobalamin). It is a different test with different numbers, so don't compare it with total B12.
Reference doses
There is no upper limit for B12, because the body absorbs only a little from each dose and passes the rest. Reference doses for adults:
- Under 200 pg/mL: 1,000 mcg a day
- 200 to 299 pg/mL: 500 mcg a day
Methylcobalamin and cyanocobalamin both work. Take it in the morning; some people find it a little energising.
Folate and B12 go together
Folic acid can raise blood counts and hide a low B12. If your report has folate but no B12, test B12 too before taking folic acid on its own. Our results screen adds a note when this happens.
Food sources for vegetarians
- Milk, curd, buttermilk and paneer every day
- Eggs, if you eat them
- Fortified foods: some breakfast cereals, plant milks and nutritional yeast
Even with these, many vegetarians do best with a supplement. Retest after about 3 months to see where you've landed.
See where you stand
Upload your report and Beyond Humans reads your B12, flags low normal values most labs print as fine, and gives you a plain language plan.
General information, not medical advice. Check with a doctor before starting any supplement, especially if you are pregnant, take medicine or have a health condition.