DEAR DR. ROACH: My daughter is a registered nurse, and tells me that when getting blood tests, it is not necessary to fast eight to 12 hours even though my doctor says to do so. Four hours is enough, she claims. Is this true, or is my daughter trying to be a doctor, if you know what I mean? -- L.C.
ANSWER: I probably agree with your daughter the nurse more than I do with your doctor in this case. Most routine blood testing does not require fasting. There is controversy about whether cholesterol testing is best done fasting or not: Most recent evidence suggests that fasting is not necessary. However, many physicians still continue to use fasting levels, as that is what they are used to. Nonfasting numbers may reflect the true state of risk to the arteries more so than fasting levels.