REBUTTAL: Chemicals in the body have a healthy range. When they're too high or too low it makes us sick, whether it's LDL or something else. When LDL is too low there is an increased risk of infection and stroke. If it's too high, there's an increased risk of atherosclerosis and heart attack.
Based on modern hunter gatherers and free living mammals, normal LDL levels are 50 to 70 mg/dl. Americans average about twice as much. Elevated LDL is not just associated with heart disease, it's a major cause and the mechanism is known. How does LDL cause atherosclerosis? Dietary saturated fat causes LDL receptors on the surface of the liver to down regulate. This interferes with the cells ability to take in LDL and this causes the level in the blood to go up. In the blood, lipoproteins with apo B (mainly LDL) adhere to the surface of the artery wall where they can diffuse inside the wall. The greater the concentration of apo B lipoproteins in the blood the greater the diffusion into the artery wall. Once inside the wall, LDL becomes oxidized. Oxidized LDL causes inflammation which attracts macrophages. They devour the oxidized LDL and become foam cells. Then the foam cells produce more inflammatory chemicals causing even more inflammation. They grow and eventually rupture depositing cholesterol crystals inside the artery walls. Then cholesterol crystals in the plaque penetrate the artery wall causing even more inflammation. LDL and inflammation are partners in crime. There is no inflammation or atherosclerosis without elevated LDL.
These changes make clots more likely to form. Very small clots contribute to plaque build up. Large clots cause heart attacks or strokes.
