Is anemia from B12 deficiency a life-threatening condition?

Not if treated. It takes a very long time for you to get near death from B12 deficiency. The treatment is so simple and effective, why chance it?
Depends. On in the same way a heart attack or a stroke is, but it can certainly decrease your health and contribute to illness.

Related Questions

Can there be a link between anemia and B12 deficiency?

Yes. Deficiency of B12 causes megaloblastic anemia. If you are deficient in b12, please discuss replacement by injection, with your doctor. B12 deficiency can also affect the nerves.

B12 deficiency, B12 shots regularly, but B12 continues to drop dramatically between each shot. Underlying cause? (no anemia or other issues)

Likely Many Misleads. B12 deficiency takes ~2 decades (eventually pernicious anemia) to be obvious. Like all vitamins, only a helper molecule for larger/more-complex protein enzymes; very widely present in nearly all foods (humans have have lost typically a single gene needed to make the vitamin). If being injected, likely not B12 or dose so low as to be irrelevant; check B12 before ; a few days after injection.

Can B12 deficiency lead to anemia and memory loss?

Yes. Pernicious anemia is the most common reason for unexpected B12 deficiency. Lack of B12 can cause both anemia and neurological damage. The latter includes numbness, gait problems, and dementia. The neurological findings can occur before there is any anemia, or vice versa. The anemia will reverse with treatment. The neurologic problems may not correct completely with B12 treatment.

I was wondering is B12 deficiency the same as pernicious anemia?

Related. Technically, pernicious anemia (pa) is due to low B12 levels caused by changes in the stomach resulting in decreased ability to absorb the B12 from a lack of something called "intrinsic factor." there are other causes of B12 deficiency that technically are not pa. Today, tests can find B12 deficiency before someone has symptomatic anemia so deficiency by itself is not always pa.

Can tea be bad for you if you have a B12 deficiency or penicious anemia? Or not help your blood count?

You're okay. Tea contains tannins that interfere some with iron absorption in folks who are iron deficient. Too much can make you sick, as with many other things. It's not going to impact an anemia caused by B12 deficiency from any cause.