I’ve seen people here on the site sometimes complaining about leg cramps or muscle cramps…
A recent study found high-dose (180mcg) vitamin K to dramatically reduce nighttime leg cramps in older men and women.
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FWIW, I used to get leg cramps at night, though it wasn’t a regular occurance, even though I was taking 90mcg MK-7 K2 (Jarrow) for years (10+). I could never trace it down to anything, I took magnesium supps etc. and I doubt it was anything with electrolites. During times when I would get night cramps, I had cramps in general, during the day, like feet, hands, even core muscles. The only big factor seemed to be getting older, as cramps were not a thing until well past 50 
… but, and this is a “maybe”, there may have been a correlation with more intense exercise while cutting back on calories.
Then, since a few years back, the night leg cramps stopped completely, and daytime cramps too, unless I specifically stress flex my feet by tensing toes in awkward positions. Why all that stopped (or started!) I don’t know. There were too many changes in my supplements and exercise routine to isolate any specific factor. That said, a few years ago, I did change my vitamin K supplement regimen, specifically after seeing Michael Lustgarten’s video on vitamin K1:
That was vitamin K1, and there are many confounders (f.ex. K1 is in veggies, so are the good effects down to the K1, or the high intake of veggies), but I thought that since I don’t supplement with K1, maybe it’s worth doing so, since there are few downsides. But since I was taking K2 from Jarrow, I thought why not get a supp that combined both. I tried a couple of brands, but eventually settled on Life Extension Super K, which has 1500mcg of K1, 1000mcg MK-4 K2 and 100mcg MK-7 K2. Now, I don’t take it at night, but more early afternoon, around 2-4pm, with my first meal, and MK-4 lasts only a few hours in blood compared to MK-7, and I have no idea which 180mcg K2 they used in that study, as that link does not specify.
I never connected the K2 intake with my night cramps disappearing, but I guess who knows.
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