Talk:Vitamin K

Conversion of Vitamin K2 to Vitamin K1

The article discusses conversion of Vitamin K1 to Vitamin K2 but does not address conversion of Vitamin K2 to Vitamin K1. Supplements of Vitamin K2 are considered desirable, but it is important to know whether these supplements satisfy the need for Vitamin K1. ---76.130.134.87 (talk) 14:57, 22 August 2022 (UTC)

Do we even know of a need for Vitamin K1 specifically? Artoria2e5 🌉 08:13, 17 April 2024 (UTC)

Medical uses: which K?

The section "medical uses" is currently very vague on which form of vitamin K is used. That feels like a thing to be clarified, and in some cases, a deviation from the sources.

• The newborn review only deals with injection of K₁.
• The warfarin article Tomaselli2017 only vaguely says "vitamin K", BUT among the sources it cites, the only one that deals with giving K in response to warfarin is "Characterizing the severe reactions of parenteral vitamin K1".
• The Bateman & Page rodenticide article only vaguely says "vitamin K" in the "Management" section... BUT again:
  • the mention of IV anaphylaxis strongly suggests that the authors treat the term as a synonym of K₁. The associated ref makes the same mistake in the title; I cannot access the text right now.
  • Bateman & Page Ref 12 seems to use K₁ and K interchangeably in the abstract. I cannot access the text right now.
  • B&P ref 16 uses both K₁ and just "K". It has its own layer of refs to chew through: some mention K1 directly in the title, others just say "K".
    • The HG Watson 2008 article referenced compares Orakay (K1), menadiol sodium phosphate (! "K4"), and Konakion (K1). That's the first mention of a not-K1 I've seen.
  • I did not check any other refs.
• The "side effects" subsection is excellent.

I believe the distinction does matter for two reasons:

• There is a known difference in side effect with the IV route, already described in the article.
• The article does not provide evidence that different forms of K are equivalent in strength when given orally. It actually hints at the opposite, as the infant and the warfarin sections specifically talk about dietary K₁, not dietary K in general. (What little we know about the minimum effective oral dose of menatetrenone [MK-4] also show that there really is a damn huge difference.)

(On the medical standaridization side: the WHO EML only lists K1, under the name Phytomenadione. The WHO ATC-DDD lists both B02BA01 K1 and B02BA02 K2 K3, though again what little we know about MK-4 shows that there's also a damn huge difference among K2 of different lengths.)

-- Artoria2e5 🌉 08:45, 17 April 2024 (UTC)

All valid issues, and calls for a close read of the existing references and potentially a search for additional references. David notMD (talk) 19:31, 17 April 2024 (UTC)

Sourcing Information in Tables

It has come to my attention that nutritional tables in the article Vitamin K contain numbers which are unsourced, or improperly referenced, or perhaps even fabricated.

Examples:

1. False Attribution? Table 1 in section "Sources", Vitamin K#Sources: Note that the first table is attributed to source #1, the "Fact Sheet for Health Professionals" (2021) from NIH.gov. Yet the table items for Cabbage, Asparagus, Kiwifruit, and Chinese Cabbage do not appear in that NIH article.
2. Crossed References? Table 2 in section "Sources": The second table is attributed to source #6, the "USDA National Nutrient Database for Standard Reference Legacy" (2018) from USDA.gov. This reference seems to be the source for Kale, Broccoli, Cabbage, Asparagus, Kiwifruit, and Chinese Cabbage in Table 1.

iirc, it is Wikipedia policy that articles which may impact the health of the reader must be held to a higher standard of accuracy than this. Perhaps a better policy (for Wikipedia, and for readers) would be to delete/ignore the tables and simply link to the trusted sources.

Page History shows that these errors have been accumulating for many months. Since this article is seemingly not being policed for accuracy, I'm considering requesting that the article Vitamin K be stripped of its "Good Article" status under the WP:GA/R procedure. ~2026-24497-32 (talk) 23:29, 20 April 2026 (UTC)

Several variables may affect the table of vitamin K content (phylloquinone) in foods shown in the article: 1) when the measurement and source occurred (the USDA has been reporting values for decades, with the results of new samples appearing periodically over years), 2) raw vs. frozen vs. canned vs. dried vs. cooked, 3) amount in a typical serving (half cup, full cup, 100 g), 4) the specific source and its date selected.

In the article table, we have both half cup and full cup amounts (don't know why, but a user can interpret the difference).

This 2018 USDA table is likely the "gold standard", but the current USDA FoodData Central for boiled spinach, as an example dated in 2019, shows the vitamin K value was determined in December 2002.

Over years, the NIH Office of Dietary Supplements and Linus Pauling Institute of Oregon State University have used the USDA FoodData Central tables.

With Special:Diff/1350285416, I removed a few items from the K1 sources table (choices are subjective; simpler is better). Perhaps IP user 2026-24497-32 can review these and edit - WP:BEBOLD. Zefr (talk) 02:55, 21 April 2026 (UTC)