The Story Behind the Missing B Vitamins
The B-vitamin complex was initially believed to be a single vitamin, but researchers later discovered it was a group of chemically distinct compounds. As new compounds were identified, they were assigned numbers, but some were later removed from the official list of vitamins for not meeting specific criteria. These retired numbers include B4, B8, B10, B11, and B14.
The Criteria for a True Vitamin
For a compound to be classified as a vitamin, it must meet specific criteria. A vitamin is an organic, essential micronutrient that the body cannot synthesize itself and must be obtained from the diet. If a compound can be produced by the body, or if research disproves its essential nature, it is stripped of its vitamin status. This process of scientific refinement and reclassification is why the numbered B-vitamin sequence is incomplete.
The Historical Search for New B Vitamins
Scientists assigned vitamin designations to substances isolated from biological materials during early vitamin research. Later research often showed these substances were either non-essential or not single compounds, leading to reclassification. For example, Vitamin B4 (adenine) and B8 (inositol) were reclassified after it was found that the human body could synthesize them.
The Confusion Surrounding Vitamin B14
References to "vitamin B14" often arise from misunderstandings or historical claims about unproven substances. Historically, a substance isolated from human urine was referred to, which was believed to increase bone marrow cell proliferation, but it was never established as a legitimate vitamin. Another theory suggested "B14" was a combination of retired B10 and B11, a claim also lacking scientific validation. The primary source of modern confusion is often supplement marketing.
Pyrroloquinoline Quinone (PQQ)
Some supplement companies market pyrroloquinoline quinone (PQQ), an antioxidant, as "vitamin B14". PQQ is a coenzyme in certain bacteria and foods and is thought to support cellular energy. However, it is not considered an essential dietary vitamin according to official nutritional guidelines. Its "vitamin" label is primarily for marketing, not scientific classification.
The Fate of Other Disproven “B Vitamins”
Looking at the history of other discarded B vitamins helps explain why B14 is not recognized. These cases demonstrate the rigorous scientific process needed to confirm a nutrient's essential status.
Pangamic Acid (Vitamin B15)
Pangamic acid, or "vitamin B15," was promoted in the mid-20th century as a remedy for various ailments. Allegedly found in apricot seeds, this substance has been difficult to reproduce, lacks known nutritional properties, and is considered unsafe by the FDA due to insufficient evidence and potential safety issues.
Para-aminobenzoic acid (PABA)
Once called "vitamin Bx," PABA is a compound the body can synthesize, making it non-essential and not a vitamin. It is a part of the folic acid molecule and supports bacterial growth. Although not essential for humans, PABA was included in historical B-complex supplements. Today, it is mainly known for use in some sunscreens, and high doses can cause side effects.
Comparison of True vs. Historical "B Vitamins"
| Feature | True B Vitamins (e.g., B1, B12) | Discredited “B Vitamins” (e.g., B14, B15) |
|---|---|---|
| Essentiality | Must be obtained through diet as the body cannot produce them in sufficient quantities for health. | Not essential nutrients for human health; the body may synthesize them or they have no nutritional role. |
| Chemical Identity | Each has a well-defined and reproducible chemical structure. | Often have ambiguous or unproven chemical identities, leading to inconsistent formulations. |
| Regulatory Status | Recognized and regulated by health authorities for dietary intake and fortification standards. | Unrecognized and potentially unsafe, with regulatory bodies like the FDA issuing warnings against them. |
| Scientific Evidence | Benefits and deficiency diseases are well-documented through controlled, peer-reviewed studies. | Claims are often anecdotal and lack significant scientific support from controlled experiments. |
Conclusion: No Vitamin B14, Just Good Science
Vitamin B14 is not a recognized, legitimate nutrient. Its absence from the official list illustrates the scientific process of classifying nutrients. As nutritional knowledge advances, compounds once thought essential are reclassified. While supplement marketing might use the term "vitamin B14," the official B-complex includes only eight members. The essential B vitamins are B1, B2, B3, B5, B6, B7, B9, and B12, which are vital for human health. For accurate nutritional information, rely on validated sources and healthcare professionals.
For additional details on the recognized B vitamins and their roles, the National Institutes of Health (NIH) is a reliable source, often found in resources like PubMed and MedlinePlus.
Frequently Asked Questions
Question: What are the eight official B vitamins? Answer: The eight official B vitamins are B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin).
Question: Why are some B vitamin numbers missing? Answer: The missing numbers (like B4, B8, B10, B11, B14, and B15) were assigned to substances initially believed to be vitamins but later found to be non-essential or not single, definable compounds.
Question: Does pyrroloquinoline quinone (PQQ) count as vitamin B14? Answer: No, PQQ is not a recognized vitamin by nutritional bodies. Although biologically active and sometimes marketed as "B14," this is a marketing term, not a scientific classification.
Question: Is Pangamic Acid (Vitamin B15) a real nutrient? Answer: No, Pangamic acid, also known as "vitamin B15," is not a recognized nutrient. Health authorities have called it a "quack remedy" due to unproven health claims and safety concerns.
Question: Why was PABA once called a B vitamin? Answer: PABA, or para-aminobenzoic acid, was once mistakenly designated a B vitamin before it was discovered the human body can synthesize it, meaning it's not an essential nutrient.
Question: Are B vitamins safe to take as supplements? Answer: Most B vitamins are generally safe in supplements within recommended guidelines; they are water-soluble, and excess is typically excreted. However, high doses of some can cause side effects, so consult a healthcare professional.
Question: Where can I find reliable information on vitamins? Answer: Reliable information can be found from authoritative sources like the National Institutes of Health (NIH), MedlinePlus, and peer-reviewed scientific journals indexed in PubMed.
