High-density lipoprotein and low-density lipoprotein are commonly referred to as the two "types" of cholesterol, but in reality, they're cholesterol transporter particles. Having a low ratio of LDL to HDL is healthier for your heart than a higher ratio; high LDL generally increases your risk of cardiovascular disease, heart attack and stroke, while high HDL decreases these risks.
Cholesterol Levels
When you have your cholesterol measured, your doctor is determining four different levels: LDL, HDL, triglycerides and total cholesterol. LDL is low-density lipoprotein, and is commonly called "bad" cholesterol, while HDL is high-density lipoprotein, and is commonly called "good cholesterol. Triglycerides are free fats in the bloodstream, and your total cholesterol is the sum of HDL, LDL and one-third of your triglycerides.
Cholesterol "Types"
Technically, HDL and LDL aren't different kinds of cholesterol. Instead, they're particles that transport cholesterol in opposite directions in the body. LDL carries cholesterol from your liver to the body cells, while HDL carries it from the body cells back to the liver for excretion. Since too much cholesterol in your body increases your risk of heart disease, it's healthy to have low LDL, but high HDL.
LDL to HDL Ratio
Your ratio of LDL to HDL provides some indication of your cardiovascular disease risk; the higher the ratio, the greater the risk, while lower ratios indicate decreased risk to a certain extent. The problem is that even if you have a low LDL to HDL ratio, if your LDL is above 100 mg/dL, you're at increased risk of cardiovascular disease, notes the American Heart Association.
Absolute Numbers
According to the American Heart Association, your absolute cholesterol levels are far more important in determining your cardiovascular risk than your LDL to HDL ratio, or your cholesterol ratio, which is total cholesterol divided by HDL. Regardless of ratio, you should shoot for LDL below 100 mg/dL, and HDL above 60 mg/dL. HDL lower than 50 mg/dL in women -- or 40 mg/dL in men -- is associated with increased risk of heart disease regardless of ratio.
References
- "Human Physiology"; Lauralee Sherwood, Ph.D.; 2004
- American Heart Association; What Your Cholesterol Levels Mean; April 2011
- American Heart Association: Cholesterol Ratio
