Who Split Vitamin B Into Eight, and Why the Story Keeps Changing

The B vitamins were not found as eight separate things. Yeast prevented both beriberi and pellagra, so one water-soluble factor looked like one vitamin until heat tests and chemistry split it into the numbered list NIH covers today.

The history of B vitamins starts with one water-soluble factor that turned out to be at least two. Yeast could prevent both beriberi and pellagra, so the factor looked like a single substance. Heat showed otherwise. By the 1920s, the factor against nerve disease was destroyed by heat, while the factor against pellagra was not. That split is where the numbering begins. ## Beriberi was known for millennia before the diet link appeared According to [PubMed](https://pubmed.ncbi.nlm.nih.gov/19892133/), a 2010 review by Lanska says beriberi was known in Asia for millennia, but a European did not describe it until the 17th century, when Brontius reported it in the Dutch East Indies. The diet link came through an animal model. In 1889, Christiaan Eijkman, working in Java, found that a nerve disease in chickens could be cured or prevented with unpolished rice or rice polishings. By 1901, Grijns had proposed a dietary deficiency explanation for beriberi itself. In 1929 the Nobel committee honored Eijkman "for his discovery of the antineuritic vitamin" ([Nobel Prize](https://www.nobelprize.org/prizes/medicine/1929/summary/)). ## The names used before the numbers settled By the 1920s, "water-soluble B" was no longer treated as one substance ([Lanska 2012](https://pubmed.ncbi.nlm.nih.gov/23183297/)). The factor against nerve disease was called the "antipolyneuritis factor," and the heat-stable factor against pellagra was the antipellagra factor. Several names were proposed for the two, but vitamins B1 and B2 were used most widely. In 1937, Elvehjem isolated the P-P (pellagra-preventive) factor, identified it as nicotinic acid, and showed that nicotinic acid cured black tongue in dogs ([Lanska 2010](https://pubmed.ncbi.nlm.nih.gov/19892133/)). ## Which vitamin came first, and what each one does Thiamin and niacin were the early threads, because each was tied to a disease before its chemistry was known. Thiamin was crystallized in 1926 and synthesized in 1936. Goldberger's pellagra studies ran from 1914 to 1929, and the niacin identification came in 1937 ([Lanska 2010](https://pubmed.ncbi.nlm.nih.gov/19892133/)). Biotin and pantothenic acid came later, through the study of microbial growth factors ([Lanska 2012](https://pubmed.ncbi.nlm.nih.gov/23183297/)). Vitamin B12 was isolated in 1947, and its structure was worked out by 1955 ([Lanska 2010](https://pubmed.ncbi.nlm.nih.gov/19892133/)). | Vitamin | Active form (NIH ODS) | Milestone in the history | | --- | --- | --- | | B1, thiamin | Thiamin diphosphate, a cofactor for five enzymes | Crystallized 1926, synthesized 1936 | | B2, riboflavin | FMN and FAD, two major coenzymes | "Vitamin B2" label for the heat-stable factor | | B3, niacin | NAD and NADP | P-P factor identified as nicotinic acid in 1937 | | B5, pantothenic acid | Coenzyme A and acyl carrier protein | Recognized through microbial growth factor work | | B6, pyridoxine family | PLP and PMP | Esmond Snell identified pyridoxal and pyridoxamine as active forms | | B7, biotin | Cofactor for five carboxylases | Recognized through microbial growth factor work | | B9, folate | Coenzyme or cosubstrate in single-carbon transfers | Macrocytic anemia recognized in the 1920s, folic acid isolated in the 1940s | | B12, cobalamin | Cofactor for methionine synthase and L-methylmalonyl-CoA mutase | Isolated in 1947, structure worked out by 1955 | Active forms come from [NIH Office of Dietary Supplements fact sheets](https://ods.od.nih.gov/factsheets/list-all/). Milestones come from Lanska's 2010 and 2012 reviews and a [2010 Snell profile](https://pubmed.ncbi.nlm.nih.gov/20353954/), all indexed in PubMed. NIH's niacin fact sheet offers one striking number: more than 400 enzymes need NAD, more than any other vitamin-derived coenzyme ([NIH ODS niacin](https://ods.od.nih.gov/factsheets/Niacin-HealthProfessional/)). The NAD side of the story has its own [NAD longevity guide](/health/nad-longevity-complete-guide). Some supplements sell vitamin B6 as P5P, pyridoxal 5'-phosphate, which [NIH lists](https://ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/) as one of the two active coenzyme forms. [P5P 50 mg](https://mtangelvitamins.com/products/p5p-50mg-vitamin-b6-supplement?utm_source=learn_hub&utm_medium=content&utm_campaign=blog_post&utm_content=history-of-the-b-complex-from-one-factor-to-eight) lists 34 mg of vitamin B6 from 50 mg of P5P in each capsule, with 60 capsules to a bottle. ## Why the numbers skip, and why the B vitamins ship together The numbers stopped matching single substances once the B2 label broke up. Lanska's 2012 review says vitamin B2 "was ultimately found to be a complex of several chemically unrelated heat-stable factors, including niacin, biotin, and pantothenic acid" ([DOI](https://doi.org/10.1159/000343115)). After that, a number on the list no longer pointed to one molecule. NIH now publishes fact sheets for the eight numbered B vitamins, from B1 through B12. All of the B vitamins are water soluble, according to [NIH's riboflavin fact sheet](https://ods.od.nih.gov/factsheets/Riboflavin-HealthProfessional/), and several share energy pathways. FMN and FAD play major roles in energy production, and NAD carries potential energy from carbohydrates, fats and proteins toward ATP. For the energy side in more depth, read the [mitochondrial health guide](/health/mitochondrial-health-complete-guide). NIH also notes that severe riboflavin deficiency can impair the metabolism of other B vitamins, because flavin coenzyme levels fall. The [biotin](https://ods.od.nih.gov/factsheets/Biotin-HealthProfessional/) and [pantothenic acid](https://ods.od.nih.gov/factsheets/PantothenicAcid-HealthProfessional/) fact sheets list B-complex combinations as one way these vitamins are sold. ## Which early labels did not hold up Some early labels did not survive as single things. The "vitamin B2" label covered several unrelated factors by the time of Lanska's review. The P-P factor is another case: Elvehjem's identification replaced a descriptive name with a chemical one, nicotinic acid. Claims are a different category. NIH says biotin deficiency is rare, and it describes hair, skin and nail claims as "supported, at best, by only a few case reports and small studies" ([NIH ODS biotin](https://ods.od.nih.gov/factsheets/Biotin-HealthProfessional/)). **Bottom line.** Water-soluble B looked like one vitamin because yeast prevented both diseases. Heat, then chemistry, pulled it apart. The eight numbers on today's list are what remained, and some names used along the way were replaced by chemical ones. ## Frequently asked questions ### Why did vitamin B look like one factor for so long? Yeast prevented both beriberi and pellagra, so one factor seemed to explain both. Heat tests in the 1920s showed it was more than one factor ([Lanska 2012](https://pubmed.ncbi.nlm.nih.gov/23183297/)). ### Which B vitamins were identified first, and in what order? Thiamin and niacin were the early threads, tied to beriberi and pellagra. Thiamin was crystallized in 1926 and niacin identified in 1937. Biotin and pantothenic acid came later through microbial growth factor work, and B12 was isolated in 1947. ### Which names were used before the B numbers settled? "Water-soluble B," the antipolyneuritis and antipellagra factors, and vitamins B1 and B2 for the two heat groups. The P-P factor later became nicotinic acid. ### Why are there gaps in the B numbering? Vitamin B2 proved to be a complex of several unrelated factors, including niacin, biotin and pantothenic acid. One number stopped mapping to one substance. ### Which vitamins work as coenzyme precursors? All eight. The table above lists the active form or cofactor role NIH names for each one. ### Why do B vitamins often come together in one product? They are all water soluble, and several share energy pathways, so the grouping has a chemical logic. NIH lists B-complex combinations as one way biotin and pantothenic acid are sold. ### Which early B candidates did not survive the science? The single-factor "vitamin B2" label and the P-P name did not survive. NIH says biotin's hair, skin and nail claims are supported, at best, by a few case reports and small studies. Thiamin went from a chicken experiment in Java, which Lanska dates to 1889, to a synthetic compound in 1936. **Next reads** - [Our NAD longevity guide](/health/nad-longevity-complete-guide): the reference page for niacin's role as the NAD coenzyme. - [The B12 history post](/blog/history/history-of-vitamin-b12-from-liver-cure-to-cobalamin): the liver cure that led to cobalamin. ### Related reading - [the B vitamin history](/blog/history/history-of-vitamin-b12-from-liver-cure-to-cobalamin) - [the B-complex split](/blog/history/history-of-biotin-from-egg-white-injury-to-vitamin-h) - [the B-complex split](/blog/history/history-of-niacin-b3-from-pellagra-to-flush) - [the B-complex split](/blog/history/history-of-pantothenic-acid-b5-from-everywhere-vitamin) - [the B-complex split](/blog/history/history-of-riboflavin-b2-from-yellow-enzyme) - [the B-complex split](/blog/history/history-of-thiamine-b1-from-beriberi-to-eijkman) - [the B-complex split](/blog/history/history-of-vitamin-b6-from-pyridoxine-to-p5p) - [the full B vitamin list](/blog/history/history-of-folate-from-lucy-wills-to-fortified-bread)