You need both Omega 3 n Omega 6 which are essentiallly EFA's - the linoleic and linolenic acids.
Most of them can be found in fish (salmon is a good source) oils but I prefer the botanical source, eg., flax seed. We do not normally consume enough Omega 3 and do need to take supplements for it. These help reduce LDL (bad cholesterol) and keep the HDL (good cholesterol).
70-80% of the cholesterol is produced by the liver and the remainder from food. So maintaning a healthy liver is very essential. I believe a good blend of botanical oils could assist you in the management of your cholesterol. Of course, you must not forget the other things like good diet, lots of water, exercise n exercise n exercise! Nothing can substitute that!