Is B11 the Same as B12? The Definitive Guide to Their Differences

November 20, 2025 •

4 min read

The B-vitamin family consists of eight distinct vitamins, but confusion often arises from different naming conventions, such as the less common term B11. This raises a key question for many: is B11 the same as B12? They are not; they are two separate compounds, each with unique biological functions essential for human health.

Quick Summary

B11 is an alternate name for folate (vitamin B9), while B12 is known as cobalamin, making them different vitamins. While both are crucial for DNA synthesis and red blood cell formation, they serve unique functions and require distinct dietary sources.

Key Points

Not the Same: B11 is an alternate name for folate (B9), while B12 is cobalamin; they are chemically and functionally distinct vitamins.
Folate's Role: B11, or folate, is crucial for DNA synthesis, cell division, and is especially important during pregnancy to prevent neural tube defects.
Cobalamin's Function: B12 (cobalamin) is essential for nervous system health and the proper formation of red blood cells.
Different Sources: B11 (folate) is found in leafy greens and fortified grains, while B12 (cobalamin) is almost exclusively found in animal products like meat and dairy.
The Masking Effect: High intake of folic acid (synthetic B11) can mask the anemia of a B12 deficiency, delaying diagnosis and potentially leading to irreversible neurological damage.
Synergy: Folate and B12 work together in metabolic pathways, highlighting the need for a balanced intake of all B vitamins for optimal health.

Understanding the B-Vitamin Complex

All B vitamins are water-soluble nutrients that play vital roles in cellular metabolism, energy production, and nerve function. However, the 'B' designation is not a single entity but a group of chemically distinct compounds. While B1, B2, B3, B5, B6, B7, B9, and B12 are officially recognized, some historical or regional naming conventions included numbers like B10 or B11, which are now largely obsolete or refer to other B vitamins. The crucial point of clarification is that B11 and B12 are not interchangeable.

What is Vitamin B11 (Folate)?

Vitamin B11 is an outdated name for folate, also known as vitamin B9. This essential nutrient is vital for cell growth, DNA synthesis and repair, and the production of red blood cells. A key function is its role in one-carbon metabolism, where it acts as a coenzyme in transferring single carbon units in various biochemical reactions.

Dietary Sources: Naturally occurring folate is abundant in many foods, particularly green leafy vegetables (like spinach and kale), citrus fruits, legumes (beans, lentils), and nuts.
Synthetic Form: The synthetic version, folic acid, is often added to supplements and fortified foods like cereals and bread.
Crucial for Pregnancy: Adequate folate intake is especially critical during pregnancy to support fetal development and prevent neural tube defects such as spina bifida.
Deficiency: A deficiency can lead to megaloblastic anemia, where red blood cells are abnormally large and immature, and can cause fatigue and memory problems.

What is Vitamin B12 (Cobalamin)?

Vitamin B12, or cobalamin, is a unique and complex vitamin that is essential for a wide range of bodily functions. It is required for the formation of healthy red blood cells, DNA synthesis, and proper neurological function. B12 is distinct from other B vitamins because it contains the mineral cobalt.

Dietary Sources: Unlike most other vitamins, B12 is produced by certain bacteria and is found almost exclusively in animal products, including meat, fish, eggs, and dairy. People following strict vegan or vegetarian diets are at high risk for B12 deficiency unless they consume fortified foods or supplements.
Absorption Process: The body's absorption of B12 is a complex process that relies on a protein called intrinsic factor, which is produced in the stomach. Impairment in this process, such as with pernicious anemia, can lead to deficiency even with adequate dietary intake.
Storage: The body has a remarkable ability to store vitamin B12 in the liver for several years, which means it can take a long time for a deficiency to manifest.
Deficiency: A deficiency can lead to megaloblastic anemia (similar to folate deficiency) and serious, potentially irreversible neurological problems like nerve damage and memory loss.

The Critical Relationship and Distinction

While B11 (folate) and B12 (cobalamin) both play a role in red blood cell formation and DNA synthesis, a significant issue arises from their metabolic interaction. Folic acid, the synthetic form of folate, can correct the anemia caused by a B12 deficiency, but it will not prevent or treat the associated neurological damage. This 'masking effect' of high folic acid intake on an undiagnosed B12 deficiency is a major health concern, emphasizing the need to distinguish between the two vitamins.

Comparison Table: B11 (Folate) vs. B12 (Cobalamin)


Feature	Vitamin B11 (Folate)	Vitamin B12 (Cobalamin)
Primary Role	DNA synthesis, cell division, amino acid metabolism	Red blood cell production, nerve function, DNA synthesis
Alternate Names	Vitamin B9, Folic Acid (synthetic)	Cobalamin
Main Dietary Sources	Leafy greens, legumes, fruits, fortified grains	Meat, fish, eggs, dairy, fortified cereals
Origin	Plants and microorganisms	Bacteria, consumed via animal products or fortified foods
Key Component	Contains a pteridine molecule, p-aminobenzoic acid, and glutamate	Contains the mineral cobalt
Key Deficiency Symptom	Megaloblastic anemia	Megaloblastic anemia and neurological damage
Masking Effect?	High folic acid intake can mask B12 deficiency anemia	No, B12 does not mask folate deficiency issues

Synergistic Functions of B Vitamins

B vitamins do not work in isolation but operate as a complex team. The relationship between folate and B12 is a prime example of this synergy. Folate relies on B12 for the remethylation of homocysteine to methionine, a crucial step in metabolism. When B12 is deficient, this pathway is interrupted, leading to the accumulation of unmetabolized folate in a 'trap,' hindering its function and contributing to megaloblastic anemia. This biochemical reliance highlights why a healthy diet requires a balance of all B vitamins, not just focusing on a single one.

Conclusion

In summary, it is clear that B11 is not the same as B12. B11 is an outdated reference to folate (B9), a vitamin crucial for DNA and cell growth, while B12 is cobalamin, which is essential for neurological health and red blood cell production. Though they collaborate in key metabolic processes, they are distinct compounds found in different dietary sources. A balanced intake of both is necessary to prevent deficiency and avoid the potentially serious risks, such as high folate intake masking an underlying B12 deficiency and its neurological consequences. Knowing the precise roles and sources of these vitamins is key to maintaining overall health and wellness. For more information on vitamin B12, consult resources from authoritative health organizations like the National Institutes of Health.

Sources National Institutes of Health (NIH). Vitamin B12 - Health Professional Fact Sheet.

Frequently Asked Questions

In some historical or regional contexts, folate, which is more commonly and correctly known as vitamin B9, was also referred to as vitamin B11. This is not a standard naming convention, but the two names refer to the same vitamin.

The main difference is their distinct biological roles and chemical structures. Folate is primarily involved in DNA synthesis and cell division, while B12 is essential for nerve function and red blood cell production.

Yes, excessive intake of folic acid from supplements can be harmful because it can mask the symptoms of a vitamin B12 deficiency. It may correct the anemia but will not prevent the neurological damage, potentially delaying a proper diagnosis.

B12 (cobalamin) is a critical concern for vegans and vegetarians because it is found almost exclusively in animal products. They often need to take supplements or consume fortified foods to ensure adequate intake.

Folate and B12 have a crucial synergistic relationship in the body, particularly in the metabolism of homocysteine. B12 is required to activate folate, and a deficiency in one can disrupt the function of the other.

A vitamin B12 deficiency can lead to megaloblastic anemia, fatigue, and serious neurological issues like nerve damage, tingling sensations, and memory problems. Unlike folate deficiency, the neurological effects can be irreversible if untreated.

Excellent sources of B11 (folate) include leafy green vegetables, legumes, and fortified cereals. For B12 (cobalamin), the best sources are animal products like meat, fish, eggs, and dairy.