You’ve probably heard that saturated fats are really bad for you, will increase your cholesterol, will eventually lead to heart disease.
This information has been handed out by trusted sources:NHS
“Too much fat in your diet, especially saturated fats, can raise your cholesterol, which increases the risk of heart disease.”
“Current UK government guidelines advise cutting down on all fats and replacing saturated fat with some unsaturated fat.”American Heart Association
“Eating foods that contain saturated fats raises the level of cholesterol in your blood. High levels of LDL cholesterol in your blood increase your risk of heart disease and stroke.”
In the 20th century, heart disease was becoming more frequent and even today is one of the top causes of death in the developed world.
Research had shown, consuming saturated fats leads to increased cholesterol. Scientists already knew high cholesterol was linked to heart disease therefore the assumption was made that saturated fats caused heart disease.
No actual experiments or research has been done directly in humans.
This was called the diet heart hypothesis.
Saturated Fat increases LDL (The "Bad") Cholesterol, But Also HDL (The "Good") Cholesterol
To start with scientists and researches did not know there were 2 types of cholesterol, HDL good cholesterol and LDL bad cholesterol. They measured total cholesterol So having a high HDL (protective) actually contributes to a high “Total” cholesterol.
Because saturated fat raised LDL levels, it seemed logical to assume that this would increase the risk of heart disease. But scientists mostly ignored the fact that saturated fat also raises HDL.
Recent research has shown not all LDL’s are bad. There are small LDL’s which attach to arterial walls and are readily oxidised, but also large LDL’s which cannot penetrate the arteries.
Consuming higher amounts of saturated fats increase the size of LDL’s reducing the risk of heart disease.
Saturated fats raise HDL (the “good”) cholesterol and change LDL from small, dense (bad) to Large LDL, which is mostly benign. Overall, saturated fats do not harm the blood lipid profile like previously believed.