Yes, your parents did you well. Put very simply, ideally the body is designed to keep cholesterol levels in check. You need cholesterol, it is a building block for steroid hormones. But too much and you do damage. So the liver specifically has receptors on it that should monitor for a proper balance of cholesterol in the system, and take up any extra dietary cholesterol in the blood and remove it. That's the perfect scenario. In some folks, that homeostasis pattern works pretty well. In many, it does not. Not to discount diet and exercise, but man, those liver receptors matter a lot, and therefore your genetics matter a lot!