✅ What Was Vitamin B11?

“Vitamin B11” was once used as a name for Pteryl-hepta-glutamic acid—a form of folate.

In fact, depending on where you are, "Vitamin B11" has been used to refer to:

In Europe (especially the Netherlands):

• Vitamin B11 = Folate (Vitamin B9)

  • In that context, B11 was basically the same as modern B9

In some older medical literature:

• It also referred to other folate-like compounds or coenzymes related to folic acid

🧠 Why Isn’t It Considered a Vitamin Today?

Because it was renamed and absorbed into Vitamin B9 (Folate) classification:

• It isn’t distinct enough to be treated as its own vitamin

• It's just one of several folate forms involved in DNA synthesis and red blood cell formation

So technically:

Vitamin B11 = just a form of B9, and it doesn't need its own number anymore.

🚫 Is It in Supplements?

No—if you're taking folate or folic acid, you're already getting the benefits once attributed to B11.

🧠 Final Thoughts

Vitamin B11 is yet another example of how nutritional science evolves: sometimes names change as we understand more.

It may have had a name and number once, but it lives on today under the umbrella of Vitamin B9.