When I was working in oil and gas, and needed offshore physicals every year, I experimented with this becuase my cholesterol levels were at the high end: I went on a vegetarian diet, gave up drinking, really excersized every day, and lost weight.  I got retested 6 months later and there was no change in my cholesterol level.   I read a book called "Survival of the sickest" which is an interesting read.  In it, the author points out that a cholesterol test done in Winter time will always be higher than a test done durring the summer.  This is because if the relationship to sunlight, Vitamin D, and cholesterol.  Vitamin D is the only vitamin our bodies will manufacture if we dont get enough of it.  The body used sunlight and cholesterol to make it!  To studies need to be done to see if lower Vit D intake = loweer colesterol levels, if you follow my logic here.

Anyway, the acceptable level of cholesterol in the blood will keep being a lower and lower number so long as pharmacuetical companies are making drugs that help you lower it, and profiting on said drugs.  Nuff said.  Just look at what the acceptable levels used to be a few years ago compared to now....total BS