Margarine is made from VEGETABLE OIL by CHEMICALLY reacting it with HYDROGEN to harden it.
The resulting SYNTHETIC ARTIFICIAL fats produced by this HYDROGENATION process are fairly ALIEN to human biology.
So we do NOT metabolise them as well as ANIMAL source fat!
Hence we get HEAVY with this foreign FAT. Then the other conditions develop. Heart disease, cancer etc..
Vegetable oil/fat is a relatively NEW invention/extraction process. Only a few of thousand years old (olive/coconut oil). Many vegetable oils (corn, rape seed, peanut) its just a few tens of years of use. Our biology has NOT had time to adjust to this NEW souce of FAT.
EAT BUTTER.. it is the NATURAL source of FAT.