Is 14 hours fast a must before getting a lipid profile?

Q: Why do pathologists advise a 14 hour fast before taking sample for Lipid Profile. What if the patient fasts only for 10 hours or 12 hours or does not fast at all? If we do fast, does this not amount to being unfair to yourself because the state of health should be examined as the person actually is on normal days? Why is he also asked to give up on dairy products, meat and alcohol, if he has been taking this on a daily basis? Won't this give incorrect readings?

A:The components measured in the lipid profile get altered with meals, and they keep going up and down depending on the extent of intake, absorption, individual metabolism etc. Hence these values get very difficult to interpret as the cut off values then become meaningless. In order to achieve a standardization, a 14 hr fast is advised. Even though it is not physiological, based on a large number of studies it has been possible to interpret the implications of the values more precisely. In some cases a shorter fast may not achieve the same results.