04/05/2026
Even if our diet is completely free of meat, eggs, and dairy, we can still absorb too much cholesterol from our digestive tract.
Our liver can make cholesterol from scratch through a long series of reactions, which can then be packaged and end up as LDL in our bloodstream to deliver cholesterol throughout our body. We don’t want to have too much, as it can lodge in our artery walls, become oxidized, and trigger inflammation that can lead to atherosclerotic plaque and kill us.
To prevent this from happening, our liver has LDL receptors that pull LDL from our blood and get rid of cholesterol through our bile by dumping it into our digestive tract, presuming that dietary fiber will trap and ultimately flush it away.
If the cholesterol doesn’t get trapped, however, it can be reabsorbed and repackaged as LDL, then re-enter our bloodstream. The same absorption happens when we eat cholesterol. However, saturated fat is the most important dietary determinant of cholesterol because it reduces the number of liver receptors that remove LDL, so more LDL ends up staying in our blood.
Throughout evolution, we ate such an enormous quantity of plant foods that our ancient ancestors may have consumed grams of fiber in the triple digits each day. That’s more than five times that of the average American today. So, when we get five times less fiber than nature intended, much of that excess cholesterol our body tries to get rid of gets reabsorbed and can circulate back through our system. That’s why one component of the Portfolio Diet is foods like oatmeal, high in the sticky fiber that helps trap cholesterol.
Learn more about evidence-based ways to lower your LDL cholesterol in the new book, Lower LDL Cholesterol Naturally with Food, at see.nf/portfolio
PMID: 29807048, 38688104, 18985059, 9101427, 9104571
USDA, Portfolio
