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The one vitamin you need for easy bruising and menstrual clotting

Wonder vitamin beats bruising and clotting

Q: Sometimes it seems like I would bruise if a feather touched my skin. I also experience heavy menstrual clotting. Could the two be related?

Dr. Wright: In the early 1970s, I worked with a woman who struggled with similar problems–she bruised more easily than nearly anyone she knew.

Even back then, it was widely known that one of vitamin K’s major functions is to stop easy bruising. But she’d had her levels measured at the hospital where she worked, and was told it was “very close to normal,” so that couldn’t be her problem. I advised her to try flavonoids, which can also stop easy bruising by strengthening blood vessels, including tiny capillaries, so they don’t break as easily.

Two or three months later, she reported that her “easy bruising” was a little better, but not that much. With no other remedies available, I advised her to take a larger-than-usual quantity of vitamin K1, 5 milligrams daily. (At that time, the only supplemental forms of vitamin K available were vitamin K1, phylloquinone, and vitamin K3, a semi-synthetic form.)

I didn’t see her for at least another six months, when she came back about another concern. When we were done discussing that, she noted that her “easy bruising” was entirely gone, and she’d noticed one other unexpected benefit…

Her menstrual clotting–which had been extremely heavy since she’d started her menstrual periods over 20 years before–had entirely gone away. She said: “My clotting with periods had been so heavy that sometimes I missed school or work because of pain.” She just hadn’t mentioned it before because, she said, “I thought it was just normal for me. Besides, a few other women I know have the problem, too.”

After starting vitamin K, her first menstrual period was “about the same,” but her second menstrual period had somewhat smaller clots and fewer of them, her third had even fewer clots, which were, again, much smaller. By her fourth period after starting vitamin K, the clots were almost gone, and after that, they were entirely gone.

Neither of us could explain it, since the nursing and medical textbooks of the time said (as they do today) that the principal function of vitamin K is enabling blood to clot normally (without it, there’s too much easy bleeding). Yet vitamin K had not only helped take away her easy bruising, but also her menstrual clotting.

Since that time, every (yes, every) woman I’ve worked with who’s taken vitamin K for her menstrual clotting has gotten rid of the problem within a few cycles. And even though there’s no official explanation for it in medical textbooks, it appears that menstrual clotting is–for these women, at least–a symptom of not enough vitamin K.