About 20% of blood LDL cholesterol (the cholesterol fraction that your doctor worries about) is from dietary cholesterol. We know this because when we block cholesterol transport in the intestine with the drug ezetimibe, blood LDL cholesterol declines by an average of 20%. (PMID 11558859)However, most of that blood LDL cholesterol comes from the first few hundred milligrams of dietary cholesterol. Additional increases in dietary cholesterol above this amount have less impact on LDL cholesterol. In other words, the impact of dietary cholesterol on blood LDL cholesterol “plateaus” Caveat: in the average person! In a substantial proportion of the population, this plateau is much less flat and dietary cholesterol continues to raise blood LDL cholesterol! (PMID 30596814)You can see this in a paper showing that simply blocking the cholesterol receptor in a “hyperresponder” to the ketogenic diet (with a sky-high LDL cholesterol) caused a reduction of 65% in LDL cholesterol. This person continued to absorb every bit of dietary cholesterol that they consumed. This is unusual but reflects the widely varying absorption of dietary cholesterol in the population. (PMID 33191194)This can also be seen in ezetimibe clinical trials: there are some people who strongly respond to cholesterol absorption blockers, while others respond very modestly. (PMID 24725763)Take home:1.     20% of blood LDL cholesterol comes from dietary cholesterol. Completely blocking cholesterol absorption or becoming a vegan all else equal reduces blood cholesterol by 20%.2.     However, there is a plateau in how much dietary cholesterol is absorbed as the cholesterol transported becomes saturated. Thus, for omnivores, increasing or decreasing dietary cholesterol will not affect blood cholesterol by much.3.     Caveat: There are some people who respond very strongly to dietary cholesterol and continue absorbing it. There is little to no plateau! These are called hyperresponders.4.     Hyperresponders are clearly seen among people who see exceptional rises in LDL cholesterol on a ketogenic diet, as well in the ezetimibe clinical trials.Find this useful? Like, follow, share!