Cholesterol is an essential molecule in the human body that has gotten an unfair bad reputation. Terms like “good cholesterol” and “bad cholesterol” are overly simplistic and promote misunderstanding about the roles and functions of cholesterol. This article will provide an overview of what cholesterol is, why our bodies need it, how it is transported around the body, and why the labels “good” and “bad” cholesterol are misleading.
What is Cholesterol and Why Do We Need It?
Cholesterol is a lipid molecule synthesized by every cell in the human body. It serves several critical functions:
- It maintains the fluidity and flexibility of cell membranes, allowing for transport of nutrients and waste products across the membrane. Without cholesterol, cells would not have the structural integrity required for life.
- It is the precursor to many essential hormones like vitamin D, cortisol, estrogen, testosterone, and progesterone.
- It is processed by the liver into bile acids that are vital for digestion and absorption of dietary fats and fat-soluble vitamins.
Simply put, without cholesterol human life would not be possible. The fact that every cell goes through the effort of synthesizing cholesterol highlights its indispensable nature.
Transporting Cholesterol Around the Body
Since cholesterol is hydrophobic (repelled by water), it cannot dissolve in blood and be transported directly to cells that need it. To deal with this, the body packages cholesterol into lipoproteins – molecules that have a phospholipid exterior shell and an inner cholesterol core. The two main types of lipoproteins are:
High Density Lipoproteins (HDLs): HDLs are considered cardioprotective as they transport cholesterol from tissues back to the liver for reuse or excretion. Higher HDL cholesterol levels are associated with lower risk of heart disease.
Low Density Lipoproteins (LDLs): LDLs transport cholesterol from the liver to peripheral tissues. Elevated LDL cholesterol levels are associated with increased risk of atherosclerosis and heart disease if the LDL particles become oxidized and inflammatory.
The outer phospholipid shell allows the cholesterol core to move through the watery bloodstream to reach its target tissues. Without lipoproteins, cholesterol would have no way to travel around the body.
The Problem with Calling HDLs “Good” and LDLs “Bad”
This overly simplistic labeling of HDLs as “good” and LDLs as “bad” cholesterol can promote misunderstanding.
There is Only One Type of Cholesterol
Firstly, it falsely implies that HDLs and LDLs carry different types of cholesterol, when in fact all cholesterol molecules are identical regardless of the lipoprotein transporting them.
The cholesterol is not inherently “good” or “bad.” The lipoproteins have different effects, which cannot be generalized as good or bad.
HDL Levels Do Not Always Reflect Cardiovascular Risk
Secondly, while higher HDL cholesterol levels are statistically associated with lower cardiovascular risk, there is no guarantee an individual with high HDL is actually at low risk.
HDL functionality (its ability to remove cholesterol from tissues) matters more than the total HDL concentration. Dysfunctional HDL can fail to protect against atherosclerosis despite high cholesterol content.
LDLs Only Harmful if Oxidized
Thirdly, LDLs only contribute to cardiovascular disease if they become oxidized and inflammatory. Non-oxidized LDLs perform their normal function of delivering cholesterol without issue.
So LDLs are not inherently “bad.” Several factors (diet, genetics, lifestyle) determine if LDLs become atherogenic.
ApoB Better Predictor than LDL Cholesterol
Finally, the number of LDL particles (LDL-P) and content of apolipoprotein B (ApoB) are more accurate predictors of cardiovascular risk than LDL cholesterol.
ApoB indicates the total burden of atherogenic particles. Simply measuring LDL cholesterol fails to provide the complete picture.
HDL particles and LDL particles
In summary, the overly simplistic labels of “good cholesterol” and “bad cholesterol” promote misunderstanding of the nuanced biology of cholesterol metabolism and atherosclerosis. More precise terminology should be used instead:
- “HDL particles” and “LDL particles” rather than HDL or LDL cholesterol
- “Cardioprotective lipoproteins” rather than good cholesterol
- “Atherogenic lipoproteins” rather than bad cholesterol
The next time you hear “good” or “bad” cholesterol, recognize this as an outdated oversimplification. Instead, consider the differences in lipoprotein classes, their diverse functions, and the need for a nuanced approach to cardiovascular disease risk management.
Workout and Fitness News
Subscribe to our mailing list and get interesting stuff and updates to your email inbox.
Thank you for subscribing.
Something went wrong.