People started using butter last century because the health care establishment told us that butter was bad for the health and margarine was healthy.
This was proven a lie.
BTW, health officials now recognize that lard (pig fat) and tallow (beef fat) are actually healthier than margarine. So, you can start cooking with lard, tallow and rendered chicken stock.
Whole fats are actually quite healthy. They are not the cause of the obesity epidemic. Sadly, sugar, grains and highly processed vegetable oils might be the cause.
!WINE