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11 Jul 2005

i've had a squeezing pain just below my left ribcage for the past week. my doctor has suggested a cholesterol test in the past as part of a general medical check-up.

what does a fasting cholesterol test mean? how long before the test should I start fasting? and does this mean that i can't drink water during that time?
Answer 408 views

01 Jan 0001

Dear Sue,

This means that for about 12 hours before the blood is taken for the test, you must eat or drink NOTHING, EXCEPT WATER. No sweets to suck, nothing at all. Mostly this is done by having a late supper, then having the blood taken first thing the next morning – this minimises the sensation of fasting as it happens mainly while your are asleep. By taking a fasting blood sample, the lab can measure the baseline free fatty acids (FFA) in your blood. For a few hours after a meal, this level is raised whilst the digestive system is dealing with your dietary fats, and any test done then may give you an abnormally high reading. Measuring FFA is part of a complete lipogram, which should measure FFA, total cholesterol, LDL, HDL, Total/HDL ratio, Lp (a) and Homocysteine. All these readings form a pattern which the lab can interpret and give you an idea of your risk profile for cardiovascular disease.

Good luck.

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