I have been flying for 27 years and although I have urinated in countless test bottles (and one or two on board the aircraft) I don't recall EVER having had to have a blood test for anything at all (although I may have had one for the initial medical which is a bit more thorough than renewals and I have simply forgotten about any blood test at that time)
I know pilots who take statins and as far as I am aware the UK CAA and UK AMEs are entirely happy about it.
Private flying is an excellent way to demolish an inheritance.