VLDL and LDL are types of lipoproteins. Lipoproteins are particles made of protein and fat that transport cholesterol and triglycerides through the blood stream.
How do lipoproteins form?
Let's start at the beginning. You eat a food and it provides more energy (calories) than you immediately need. The liver breaks down some the carbohydrates and protein forming triglycerides (fat) and cholesterol. The liver is the major fat producing organ, while our adipose tissue (fat cells) stores the fat made by the liver.
Oil (fat) and water (blood) do not mix. To solve this problem, the liver exports the triglycerides (fat) by coating them with a protein, cholesterol, and phospholipid shell. A phospholipid shell is a structure that acts as an emulsifier so the fat and blood will mix. The resulting product is called a lipoprotein (lipo or lipid = fat).
Lipoproteins can transport different components throughout your system, such as cholesterol, fat, and protein. LDL (low density lipoprotein) and VLDL (very low density lipoprotein) transport mostly fat and cholesterol, but differ in the amount of each.
Cholesterol, triglyceride, and protein content of LDL and VLDL
The liver releases VLDL into circulation. VLDL is made up of 55 to 65 percent triglycerides, 10 to 15 percent cholesterol, 15 to 20 percent phospholipid, and 5 to 10 percent protein. (For comparison, HDL the "good" cholesterol is 45 to 50 percent protein.)
Once the VLDL is released, enzymes in the bloodstream interact with the triglycerides within the lipoprotein and change the package from "very low density" to "low density". LDL is "less dense" than VLDL because it has lost a large chunk of triglycerides, changing its concentration to 10 percet triglycerides, 45 percent cholesterol, 22 percent phospholipid, and 25 percent protein.
There is an intermediate step between the VLDL and LDL, but let's keep it simple and stick with the more general overview of what is taking place.
LDL and heart disease
If you have high LDL levels, an oxidation process takes place that leads to plaque development in your artery walls, damage to vessel linings, and heart disease. Eating a wide variety of fruits and vegetables rich in antioxidants, such as vitamin C and vitamin E may slow or inhibit this oxidation process.
LDL vs. VLDL target levels
LDL and VLDL are both "lipoprotein packages" in your blood. Both are considered "bad" types of cholesterol. They differ in what each package carries.
LDL cholesterol carries mostly cholesterol, some protein, and minimal triglycerides throughout your circulation. LDL should be less than 130 mg/dl, and ideally less than 100 mg/dl.
VLDL cholesterol contains minimal protein and mainly transports triglycerides. VLDL should be less than 40 mg/dL.
To prevent VLDL and LDL from clogging your arteries, follow a diet to lower cholesterol and consume antioxidant rich fruits and vegetables.
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