NEVER, and they keep trying and they keep failing. Of course since it is the drug companies that are trying to prove that everyone should take their drugs, when they fail you never hear about it. The latest is the ENHANCE study. Adding one cholesterol drug to another caused the cholesterol numbers to fall another 17% but the measurement of the INCREASE in growth of plaque was double. That tells you that lowering the cholesterol has no effect (or even negative effect) on plaque formation. Now this study was concluded 2 years ago but they did not release it until recently. Guess what they did for 2 years? They ran millions of ads about the two kinds of cholesterol. They captured 18% of the market for a drug that cost $4 a day and they knew it did not work any better than the $0.25 per day drug. Never artificially lower your cholesterol. If your body makes it, you need it.Now lowering it naturally is another story. As I said, if you NEED it than your body makes more, but why do you need it? Pharmacist who's life was almost ruined by Lipitor