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Do you know how much Vitamin k is in rhubarb? I have checked a few listings and have not been able to find a number on it. Thanks for any help you can give me.
According to the USDA, one stalk of raw rhubarb (about 1 3/4 ounces) contains 14.9 micrograms of Vitamin K. One cup of raw rhubarb, diced, contains 35.7 micrograms.
I looked at a variety of plain rhubarb pie recipes, and most appear to require anywhere from 4 to 6 cups of chopped rhubarb. That means that a small slice of rhubarb pie - 1/8 of the whole pie - would contain between 17.9 and 26.8 micrograms of Vitamin K in the rhubarb alone (plus whatever might be in the pie crust or other ingredients).
The somewhat more common strawberry-rhubarb pie usually calls for 3-4 cups of fresh rhubarb, which means that a single slice (1/8th pie) would contain between 13.4 and 17.9 micrograms of Vitamin K in the rhubarb alone.
If your goal is to consistently consume about 80 micrograms per day of Vitamin K (about the RDA), a single slice of rhubarb pie could be 15-20% or more of your day's allowance of Vitamin K. Something to keep in mind!
Thanks for writing,
Timothy S. Harlan, MD, FACP