Vitamin K

I just updated VeganHealth.org with a page on vitamin K. Some people have claimed that you must eat animal products in order to obtain one of the two main types of vitamin K. After reviewing the research, that does not appear to be the case. Click here to read more about it.

5 Responses to “Vitamin K”

  1. Ron Says:

    You’ve discussed the menaquinones (K2) in general, and the MK-7 form of menaquinone (in natto), but what about the MK-4 form, aka menatetranone? Interestingly, the Japanese, who have natto to be beneficial for bones, use MK-4 to treat osteoporosis. It’s my understanding that it isn’t produced by fermentation, and non-vegans get only a very small amount directly from their food, and vegans get none directly from food; we have to convert all of ours. See the article that starts on page 10: http://www.vrp.com/pdf/October2006news.pdf; it has 46 references, some of which may be of interest.

  2. Jack Norris RD Says:

    I thought this was the most interesting study:

    http://www.ncbi.nlm.nih.gov/pubmed/7596062

    I didn’t find anything more recent looking at blood levels of menaquinone-7 and bone fractures.

  3. rtyui Says:

    You’ve discussed the menaquinones (K2) in general, and the MK-7 form of menaquinone (in natto), but what about the MK-4 form, aka menatetranone?

    exactly mk-7 vs mk-4 seems crucial to explain.

  4. Florent Berthet Says:

    Jack,

    Several studie have shown that K2 (especially the MK-7 form) where very beneficial to cardiovascular health (as well as reducing all-cause mortality). Here are three examples, with some excerpts:

    http://jn.nutrition.org/content/134/11/3100.full?: The relative risk (RR) of CHD mortality was reduced in the mid and upper tertiles of dietary menaquinone compared to the lower tertile [RR = 0.73 (95% CI: 0.45, 1.17) and 0.43 (0.24, 0.77), respectively]. Intake of menaquinone was also inversely related to all-cause mortality [RR = 0.91 (0.75, 1.09) and 0.74 (0.59, 0.92), respectively]

    http://www.ncbi.nlm.nih.gov/pubmed/19179058: A high intake of menoquinones, especially MK-7, MK-8 and MK-9, could protect against CHD. However, more research is necessary to define optimal intake levels of vitamin K intake for the prevention of CHD.

    http://www.ncbi.nlm.nih.gov/pubmed/18722618?ordinalpos=30: high dietary menaquinone intake, but probably not phylloquinone, is associated with reduced coronary calcification. Adequate menaquinone intakes could therefore be important to prevent cardiovascular disease.

    Also, this article by Chris Kresser makes some good point: http://chriskresser.com/vitamin-k2-the-missing-nutrient

    What would you respond to these studies?

    Thanks in advance.

  5. Nadav Says:

    Florent,

    I also came here after reading these studies. It should be noted that they are not intervention trails, and for all we know the reduced CHD risk can be a result of some other nutrient coming from the same foods that are high in menaquinone, or from some behavioral pattern common among those who consume a lot of menaquinone.
    But it does raise a question and I hope an intervention trail (say, one based on supplements) will be done soon.

    In case it is of interest to someone, there are vegan vitamin K2 supplements, derived from natto.

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