yes it's true. It's the omega 3 fatty acids that help breakdown cholesterol and the saturated fats..
Also they contain protein and a little fibre...
Watch the ingredient list when buying peanut butter- it doesn't want to say ''salt or sugar''. Just plain old 'peanuts' should be on the ingredients list.
look at hazelnuts, brazils, walnuts, flax seeds also.
Fish like salmon, trout, sardines, mackerel...