# Talk:Nicotinic acid

I noticed in Brazil that there were some supplements that had niacin in the nutritional table, but in the ingredients it says it is actually nicotinamide.
I was sure that niacin meant nicotinic acid, so I emailed a big supplement company here. They replied to me pointing to a food/supplement labeling legislation that in summary says that niacin can refer to either nicotinic acid or nicotinamide:

ANVISA (2021-10-15). Instrução Normativa - IN Nº 28, de 26 de julho de 2018 (Com emendas) [Regulatory Instruction - No. 28, of 26 July 2018 (with amendments)] (PDF) (Report) (in Brazilian Portuguese). Archived (PDF) from the original on 2024-12-12. Retrieved 2024-12-12.
Brazil usually just mirror those kind of standards from US, so what does the FDA says?
"(...) This results in the following order for vitamins and minerals: Vitamin A, vitamin C, vitamin D, vitamin E, vitamin K, thiamin, riboflavin, niacin, vitamin B6, folate and folic acid, vitamin B12, (...) The (b)(2)-dietary ingredients shall be listed according to the nomenclature specified in § 101.9 or in paragraph (b)(2)(i)(B)(2) of this section." 21 CFR 101
"The term niacin refers to nicotinamide (nicotinic acid amide-NAD), nicotinic acid (pyridine-3-carboxylic acid), and derivatives that exhibit the biological activity of nicotinamide."

FDA (2019-08-15). Guidance for Industry: Converting Units of Measure for Folate, Niacin, and Vitamins A, D, and E on the Nutrition and Supplement Facts Labels (Report). Archived from the original on 2024-11-26. Retrieved 2024-12-12. PDF
The last document also mention some curious things:

"niacin" (...) "had its unit of measure established in the 1989 RDA as “Niacin Equivalent”"
"While the unit of measurement for the RDI for niacin is listed as Niacin Equivalents (i.e., mg NE) in § 101.9(c)(8)(iv), only the amount “mg” will continue to be declared in labeling."
NE = Niacin Equivalents, 1 mg NE = 1 mg niacin = 60 mg tryptophan (see § 101.9(c)(8)(iv) (footnote 5))
"Furthermore, the amino acid tryptophan is available for conversion to NAD once protein synthesis needs are met and thus can contribute to meeting the RDA for niacin (Ref. 1). The tryptophan-to-niacin inter-conversion was considered previously in setting the RDA for niacin (Ref. 4). Therefore, the RDA for niacin is expressed in Niacin Equivalents (NE), allowing for the conversion of tryptophan to niacin (mean value of 60 mg tryptophan is equivalent to 1 mg of niacin)"
mg NE = mg niacin + (mg tryptophan ÷ 60)
Okay, so maybe the FDA could be wrong? What academic papers say? Doing a quick search, I find that there are papers aligned with the FDA saying that niacin refers to both nicotinic acid and nicotinamide.[1][2][3][4][5]
And there are also papers aligned with the current wikipedia article, saying that niacin refers only to nicotinic acid, but not to nicotinamide.[6][7][8][9][10][11][12][13][14]
So then I find out that niacin is the USAN name of nicotinic acid, so it is the term used in some chemists websites.[15][16] 

Niacin (nye’ a sin). USP. C6H5NO2. 123.11. [Nicotinic Acid is INN and JAN.] (1) 3-Pyridinecarboxylic acid; (2) Nicotinic acid. CAS-59-67-6. Antihyperlipidemic; vitamin (enzyme co-factor). Niacor (Upsher Smith); Niaspan (KOS); Nicolar (Sanofi Aventis); Wampocap (Medpointe)
Niacinamide (nye" a sin’ a mide). USP. C6H6N2O. 122.12.[Nicotinamide is INN and JAN.] (1) 3-Pyridinecarbox-amide; (2) Nicotinamide. CAS-98-92-0. Vitamin (enzyme co-factor).
-- from "2007 USP Dictionary of USAN and International Drug Names"
But nutritionists refer to Vit B3 as niacin, as we can see in the documents by nutritional institutions:

"The term niacin is used here in the generic sense for both nicotinic acid and nicotinamide (niacinamide)." 1989 RDA 10th ed.
uses the term niacin to refer to Vit B3 - report on 1980 RDA, on 1978 RDA, on 1968 RDA, FAO/WHO
"Niacin is a generic term for nicotinic acid and nicotinamide." European Food Safety Authority (EFSA)

What a mess! Different institutions using a different definition!
We should improve this article to try to explain this messy confusion.
-- Arthurfragoso (talk) 04:18, 13 December 2024 (UTC)

The NIH-ODS fact sheet - which represents the authoritative 1998 Institute of Medicine monograph (followed by many countries), explains it clearly as "Niacin (also known as vitamin B3) is one of the water-soluble B vitamins. Niacin is the generic name for nicotinic acid (pyridine-3-carboxylic acid), nicotinamide (niacinamide or pyridine-3-carboxamide), and related derivatives, such as nicotinamide riboside." This seems adequately stated in the lede where I updated and reapplied the NIH ref. Zefr (talk) 04:44, 13 December 2024 (UTC)
Adequately stated? The lede says "Niacin, also known as nicotinic acid". -- Arthurfragoso (talk) 05:33, 13 December 2024 (UTC)
More appropriate for the Definition section than the Lead. David notMD (talk) 17:18, 13 December 2024 (UTC)
Except this does not work because in the drug context, FDA approves nicotinic acid preparations for altering blood lipids under the name "niacin". See, for example, NIASPAN label. Does the FDA disagree with the FDA, or... perhaps it's just two different senses of a word (in Am.E)? Artoria2e5 🌉 13:25, 16 December 2024 (UTC)

The article currently uses the phrase prescription niacin seven times. 
I (as a general reader on the subject) assumed that this just meant, niacin in a form (any form) that is commonly the subject of a medical prescription. But now I'm not so sure. Is it perhaps intended to mean specifically CAS 59-67-6? I think this should be clarified. Prescription niacin looks like a well-defined term, but this seems doubtful. Andrewa (talk) 02:32, 24 December 2024 (UTC)

Andrewa Prescribed (perhaps a better adjective?) niacin is dose range 500 to 3000 mg/day. In the US (and other countries?), non-prescription niacin is a dietary supplement, dose range 100 to 1000 mg/day. David notMD (talk) 18:28, 25 January 2025 (UTC)
If that information can be sourced it belongs in the article. But does it give us a clear definition of what the article means by prescription niacin, or of an alternative term?
That's what is needed. We are a general encyclopedia. Our articles should not need specialised knowledge on the part of the reader. Andrewa (talk) 21:46, 25 January 2025 (UTC)
The prescription products are Niacor and Niaspan ER (for extended release). David notMD (talk) 12:15, 30 January 2025 (UTC)

Arthurfragoso I just undid this removal of 24KB of text until we get more discussion on it. My understanding from the RM discussion is that the role of nicotinic acid as a vitamin and the effect on health is still a major part of the scope, but that edit took us from thorough coverage to a single paragraph without even a link to Vitamin B3. I'd like to see more consensus before removing a quarter of the page. — Wug·a·po·des 08:11, 30 January 2025 (UTC)

Given that Nicotinic acid retains the GA rating, I prefer that it be as complete as possible, i.e., retaining content that is also at Vitamin B3 versus readers needing to visit both articles. David notMD (talk) 04:09, 31 January 2025 (UTC)
The text does not concern nicotinic acid, but the nutritional entry. I am going to 1.5RR it. If a "GA" needs to be maintained by falsely keeping content that does not belong, then it's not a worthy GA. Artoria2e5 🌉 05:44, 17 February 2025 (UTC)
FYI: The majority of this article achieved GA status in 2020 as titled "Niacin". The name was changed in early 2025 and approximately 25% moved to Vitamin B3. David notMD (talk) 18:18, 17 February 2025 (UTC)