blood tests

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Many substances tested have diurnal variations, or are affected by
food or medication. Following are our recommendations for consistent
results that can be compared to each other.
Basic instructions
• Fast 12 hours, except for water (and HC for those who take it)
• Blood draw should be in the morning as close to 8 a.m. as possible
• Take meds and supplements normally on previous day up to 12 hours
• Morning of the blood draw, drink extra water to prevent dehydration
• Hold meds and supplements (except for HC) until after the blood draw
Special requirements in addition to basic instructions
• Get blood drawn without a tourniquet
Note: A tourniquet can cause blood cells to break and release their potassium,
causing a falsely high result. If the phlebotomist absolutely refuses, ask for a
blood pressure cuff to be used rather than a rubber band.
Iron labs
• Discontinue iron and vitamin C for five days before the blood draw
Vitamin B12
• Discontinue B12 supplements for five days before the blood draw
• Salt fast for 24 hours before testing (no sea salt supplementation, no
salt added to food, no beverages with sodium)
• Be up moving starting at 6 a.m.
• Do not take HC in the morning until after the blood draw
• Testing done at 8 a.m. sitting upright
• Test renin activity, sodium and potassium at the same time
• Pre-menopausal women test during first week of the cycle (day 3/4)
Estrogen and Progesterone for menstruating women
• Test between day 19 and 21 to see balance
• Test progesterone around day 21-23 to see peak
• Test estradiol around day 13-14 for peak