About the only "natural" remedy to lower cholesterol is niacin. But taking the needed 2000 mg or more of niacin could hardly be called natural.
I take 3000 mg of niacin a day in the prescription form of extended release, Niaspan.
The only side effect of niacin is flushing (hot flashes). That is why an extended release formula is reccomended. This bothers some greatly, and others like myself, it doesn't bother at all. You don't know until you try it.
I've never heard of Lecithin lowering cholesterol... or at least no scientific studies. You might hear the same about garlic... but about the only thing garlic lowers is your circle of friends...