Plant sterol enriched margarines increase cardiovascular risk?

Maybe the assumption that natural substances can do no harm has again been shown to be wrong. Are these margarines good or bad for you?

A case published in BMJ Case Reports this week raises an interesting question about plant sterol-enriched margarines and cardiovascular risk. They reduce LDL cholesterol but do not seem to reduce cardiovascular risk. In this report a lady developed xanthelasma 18 months into a programme of cholesterol reduction with plant sterols.

Vergès B, Athias A, Petit JM, Brindisi MC. Extravascular lipid deposit (xanthelasma) induced by a plant sterol-enriched margarine. BMJ Case Reports 2009 [doi:10.1136/bcr.10.2008.1108]

The authors point out that elevated campesterol, a plant phytosterol and the cause of the xanthelasma in this case, may promote atherosclerosis. They go on to say that their observation raises concern about potential cardiovascular risk after long-term consumption of these margarines.