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Ketostix: instrumental analysis 101
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V_Keto_V
Posts: 342 Member
According to Lexicomp: Ketostix for ketone urinalysis utilizing Nitroprusside (i.e. Color change) is not reliable for detection of Beta Hydroxybutyric acid, the ketone which compromises about 80% of total ketones when someone is in a state of Ketosis. However, Ketostix do reliably measure Acetic acetate (about 20% of total ketones). A fasted state of ketosis is typically achieved after 18 hours of fasting. Large rises in urinary ketones are detectable prior to serum ketone level elevations.
False (+)s: N-acetyl cysteine (NAC), Levodopa (L-DOPA), Ascorbic acid (megadoses of Vitamin C), Isopropanol (2-propanol for you chemistry geeks), Valproic Acid (VPA)/Divalproex (DPA), Phen-AZO-pyridine (PYRIDIUM/AZO), & Phthaleins
Thought you fellow Keto'ers would like to know some limitations of Ketostix as well as having reassurance from not achieving Ketosis according to a simple chemical reaction.
False (+)s: N-acetyl cysteine (NAC), Levodopa (L-DOPA), Ascorbic acid (megadoses of Vitamin C), Isopropanol (2-propanol for you chemistry geeks), Valproic Acid (VPA)/Divalproex (DPA), Phen-AZO-pyridine (PYRIDIUM/AZO), & Phthaleins
Thought you fellow Keto'ers would like to know some limitations of Ketostix as well as having reassurance from not achieving Ketosis according to a simple chemical reaction.
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Agreed. There is so much information out there stating the inaccuracy of Ketostix- I'm suprised so many still use them.0
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And I just bought my first package0
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Even with their limitations there is something very satisfying about that colour change!0
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Yes, the color change (not necessarily the quantity corresponding to color) can be indicative of someone being in Ketosis or not.
More limitations include exercise, excess fasting, & energy deficit...one can test negative for urinary ketones because they have all been excreted or have partitioned into the blood (again there will be a dramatic rise in urinary ketones before blood ketones rise...you will get a False (-) should you measure exercise too much, fast too long, or over diurese/over hydrate diluting urine, etc.)0
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