Some misconceptions were sold to the public for selfish reasons.
During World War II there was a push to develop an alternate to oil. Hydrogenated Vegetable Oil and margarine were created to be replacements.
After millions of dollars was spent on two failures, some use needed to be found for these products.
First, they were fed to animals. As the animals didn’t die but there wasn’t much use for them, as animals don’t need cooking oil or butter, they were repackaged and sold to humans.
To get people to toss their natural butter and Olive oil, the hype was that they were healthy. All sorts of claims were made about how they were so good for you.
Millions of people fell for this, and purchased these inferior and unhealthy products. Millions of people were deceived and held these misconceptions that these products were healthy without any real proof.
This farce when on for over 60 years, allowing the developers to recoup their expense and pocket the profits.