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.More or less undercarboxylated osteocalcin could be hangmgaround just because there's more or less total osteocalcin available to becarboxylated.Ihe researchers who developed the test provide areference range (the average upper limit for healthy people), but the testwould need to be applied to a large population to confirm the validity ofthe range.Elevated levels of ucOC, indicating a witamin K, deficiency, are asso-ciated with lower bone mineral density and higher risk of hip fracture.Levels of ucOC increase in teenagers, reflecting a greater need of witamin K,for their growing bodies, and levels spike again at menopause when thebone-boosting effects of estrogen are withdrawn.This effect is seen inwomen who undergo natural menopause and in those whose ovaries havebeen removed surgically.What is a passing mark on an ucOC test? Remember, themore undercarboxylated osteocalcin you have, the more deficient youare in K2, so the lower your ucOC score, the better.The average resultfor165MEASURING YOUR VITAMIN K LEVELSzhealthy people, according to the researchers who developed the test,is around 3.6 ng/ml (nanograms per milliliter).3 Levels of ucOC tendto spike in teenagers and menopausal women, so this rough test doesreflect the same trends of vitamin Kz deficiency we see using ratiomeasurements.Some studies noted diminished bone density withucOC as low as 1.65 ng/ml.Keeping in mind that apparently healthypeople are at risk for long-term complications of having undercar-boxylated osteocalcin, we should probably be striving for a valuebelow i.6 ng/ml.Corticosteroids and ucOC testing Corticosteroidtreatment may interfere with the results of any kind ofosteocalcin testing, including the ratio tests.Anti-inflammatory steroid medications, like prednisone, are notori-ous for their bone-density-lowering side effects.Corticosteroidslower the level of both osteocalcin and ucOC, with or withoutvitamin Kz supplementation.4 lhat means that steroids confoundthe usual association between vitamin K activity and ucOC levels, soosteocalcin testing may not be a reliable indicator of vitamin Kstatus if you are taking corticosteroids.Jhe only company currently offering the ucOC test is Metametrix.Since the test is not the desirable ratio assessment, its value is limited.Only a licensed health care professional may order the test, which iscalled the Vitamin K Assay in the company's catalog.If your doctordoesn't currently offer it, the company's user-friendly website has adownloadable form that you can bring to your doctor so he or she166VITAMIN K, AND THE CALCIUM PARADOXmay order it.Alternatively, Metametrix provides a clinician referralservice that will connect you to a practitioner in your area who workswith this lab.The Serum Osteocalcin TestAnother test, the name of which is confusingly similar to the one thatgauges KZ activity, is much more commonly available than the ucOC,so watch out you don't accidentally get this if what you really want isto measure your menaquinone status.It's the serum osteocalcin test,also called bone gla protein, or BGP, test.'nie serum osteocalcin testmeasures the amount of osteocalcin in circulation.Osteocalcin levelsare a biochemical marker, or biomarker, for the bone formation pro-cess.Serum osteocalcin levels are correlated with bone diseases likeosteoporosis, so your doctor might suggest this test to evaluate yourrisk of osteoporosis or to assess the effectiveness of osteoporosis treat-ment.Clinical trials use osteocalcin levels as a preliminary biomarker ofthe effectiveness of bisphosphonates, a class of drugs used to treatosteoporosis.The osteocalcin test is not the same as the undercarboxylated osteo-calcin test, and it won't measure your vitamin KZ status.Osteocalcintesting measures only how much of this vitamin K2-dependentprotein is present in the blood, not how much of it bas been activatedby K2.Measuring osteocalcin levels isn't a good substitute formeasuring ucOC levels because many factors unrelated to vitamin KZcan affect the test.Osteocalcin levels may increase or decrease, butthat doesn't tell you how much of the osteocalcin that is there isactivated by K2.Osteocalcin levels don't correlate with disease riskfor osteoporosis,167MEASURING YOUR VITAMIN K LEVELSzheart disease or cancer the same way ucOC levels do.Osteocalcinassessment is a useful tool in managing certain health conditions andmay be indicated for you, it just can't be used to judge whether you aregetting enough menaquinone.Should You Be Tested?Given that the only truly meaningful undercarboxylatedosteocalcin testing is currently unavailable, witamin K, deficiency iscommon and there are no known side effects of taking witamin K., theaverage person needn't bother with undercarboxylated osteocalcintesting.Just focus on a diet that includes grass-fed foods, fermenteddairy products and natto, or take a KZ supplement if your daily diet islacking menaquinone-rich foods.For you keeners out there who justlove empirical evidence, or for clinicians who suspect witamin KZdeficiency is affecting their patient's health, the undercarboxylatedosteocalcin test is an option.Bone Density ScanningWhile we're waiting for better ucOC tests to arrive on the scene,monitoring bone mineral density (BMD) is something to consider, as itgauges one of the desired benefits of taking witamin Kz.Vitamin Dintake, calcium intake, hormones and other factors all influence bonedensity, so bone density testing is not a measurement of K2 status only.However, Kz's effects on bone health are noticeable with BMD testing,which measures a crucial, though by no means unique, predictor offracture risk [ Pobierz całość w formacie PDF ]