Fasting Before Your Cholesterol Test


If you’ve had your cholesterol tested, you know the drill. You fast for at least 8 hours before the test. But a new study, published in the journal Archives of Internal Medicine found that pre-test fasting might not be necessary for many people.

The study looked at more than 200,000 people who were tested. Some fasted before the tests, while others had eaten recently. Levels of total and HDL cholesterol varied only about 2% based on whether a person fasted or not. LDL levels varied less than 10%. Triglycerides varied less than 20%.

Determining who gets which test should depend on each person’s needs. Ideally, fasting lipid profiles should be done at least once. If this is normal, you may need only non-fasting cholesterol tests for many years.

One Response to “Fasting Before Your Cholesterol Test”

  1. R Jory says:

    On the face of it, this article does not help me one bit, and based on information I see in other sources, it seems entirely bogus.

    If I am to believe what this article says, pre-test fasting is irrelevant for some segment of the population.

    How do I determine if I am one of those people for whom blood-test fating is irrelevant?

    I have had cholesterol blood-test (with 12 hour fast) done by my doctor, and the most recent one went from “high but within OK limits” to “you need to get this down or get on statins.” The nurse tried to tell me that a change from 203 to 204 represented an “increase” (she could not tell me the margin of error on blod-level readings). My readings went up 20% and my doctors office is telling me that they will prescribe Statin drugs if the next test does not decrease: we are talking a 20% change for me. You seem to write off a 20% change as not significant.

    Elsewhere, I ahve seen LDL-HDL-TriG charts taken as part of a study on diet and cholesterol levels, taken at short intervals over the course of a day. You cannot tell me that the levels are the same before meals, while eating, and in the hour or two after a meal: the charts I saw in a lecture showed clear spikes. Where are you getting your info that cholesterol doesn’t spike with meals?


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