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I've seen some studies that indicate MK4, a chemical from certain types of Vitamin K, is capable of preventing and reducing bone fractures.

I believe kale is the food with the most Vitamin K; however, I am unsure whether the vitamin K from it gives MK4 or MK7.

If you have a link, that'd be great.

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It doesn't. It relates to the "Nutrition" part of the "Fitness & Nutrition" in big letters at the top of the page. – Nick Aug 15 '11 at 16:24
Change the title of the site if you're not going to entertain questions that 50% of the title suggests. – ash Aug 16 '11 at 7:42
I don't know why you closed my question because of YOUR stupidity to not change the title of the site. – Nick Aug 16 '11 at 11:10
From the FAQ, "Topics include exercise and training, nutrition and diets" – Nick Aug 16 '11 at 11:12
Nick, @Josie we are actually currently in the process of redefining the site scope and hence also the name. If you'd like to get involved in the discussion (make a case for keeping "Nutrition" in, as we are currently going towards kicking it out) you should write an answer to the Meta question Ivo linked to above. – VPeric Aug 16 '11 at 13:24
up vote 1 down vote accepted

If I remember correctly, both MK4 and MK7 are types of Vitamin K2, whereas Kale would only contain K1, being a plant.

As far as sources go, I believe plants contain K1, animal products (meat, eggs, dairy, grass-fed butter!) contain MK4 and bacteria produce MK7, which is therefor found in fermented food (Sauerkraut, Natto! Yoghurt... ).

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I thought the body converted K1 into the MK4 form of K2? Is this not correct? – Nick Aug 15 '11 at 16:25
However, supplementation of K1 appears to have no positive effect (unless it fixes a deficiency). The body seems to convert K1 to K2 at a fixed rate, and K1 is inactive in the body. Supplementation of K2 on top of what the body produces is what's beneficial. – Waquo Aug 15 '11 at 18:40

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