No seems to be the answer. My solution to this is to drink hot
water from my coffee mug. It really helps your craving for coffee
and hydrates you as well.
- No. The most common blood tests done that require fasting are
lipids (cholesterol, LDL, HDL and Triglycerides) and fasting blood
sugar (note, glycohemoglobin does not require fasting). Of these,
the blood sugar and triglycerides are the most variable. They are
affected mostly by sugar intake. It is very important to stay
hydrated before a fasting blood test so that your blood and urine
do not falsely indicate your kidneys are malfunctioning. Although
water is best, caffeine has not significantly affected the blood
tests of my patient population.
- Depends on the test, and if it's a fasting test, but Generally
speaking no, caffeine affects liver function and releases hormones
from your adrenal glands, even decaf has caffeine in it.
- No, if you ingest anything other than water the results will be
inaccurate. Some people believe that black coffee will not have an
affect on glucose, however the caffeine alone has an impact on the
pancreas which in turn effects insulin, which effects glucose.
- I am going for a blood test tomorrow morning (consisting of a
whole range of sub-tests including cholesterol, thyroid, etc.). My
instructions were 12 hours of fasting including all solids and
liquids BESIDES water as well as black coffee in the morning...so
YES you may have BLACK coffee. Cream and sugar obviously affect
- No, just clear liquids. Hit up the tea if your desperate for
- Generally, no. You should try to drink only water.
- It depends on the test your having done. If you drink black
coffee, with no additives, you can still have fasting labs done.
However, coffee will increase your blood pressure and affect some
tests .... especially a CRP.
- Your paying for these tests. I would recommend no coffee 10-12
hours prior if your not sure. The best method is to call the
- It is best if you were not to have anything to eat or drink
before having bloodwork done or any test as such because the coffee
might change the result of the test in some way, maybe water is
- Yes. You are only supposed to drink water.