Lipid Metabolism and Diabetes

There is a direct relationship between diabetes and high lipid levels in the bloodstream.

Persons with diabetes should be aware of this connection and seek to maintain healthy cholesterol and triglyceride numbers.

Cholesterol and triglycerol are only two of the many types of lipids the body uses for its functioning.

Cholesterol

Cholesterol is produced within all cells in the body. It is a necessary component of cell membranes, required to maintain their structural integrity.

Cholesterol is a waxy substance, not readily soluble in water. Because only small amounts can dissolve into the (water-based) bloodstream, cholesterol requires some assistance to pass through. This comes in the form of lipoproteins.

There are several types of lipoproteins in the blood. The two most important to us are the low-density lipoprotein (LDL) and the high-density lipoprotein (HDL). Cholesterol is transported inside these lipoproteins but in different directions.

LDL (so-called "bad cholesterol") particles are the primary carriers of cholesterol through the bloodstream. Through a set of regular metabolic processes, these LDL molecules are used up. The body then synthesizes more.

When dysregulation of the metabolic process occurs, LDL begins to accumulate in the blood. It combines with a type of white blood cell called a macrophage. The macrophage then engorges and becomes a foamy substance that embeds into the sides of blood vessels, contributing to plaque formation.

HDL (so-called "good cholesterol") particles use a similar transport method to return unused cholesterol to the liver, where it is either excreted or re-used. The higher the number of HDL particles in the blood, the less cholesterol will ultimately be retained in the bloodstream in the form of plaque.

Triglycerides

A triglyceride is composed of glycerol and three fatty acids. Both of these elements can be metabolized to create a source of energy for cells in the body.

Triglycerides (and there are many types) serve as transporters of adipose fat and blood glucose to and from the liver. Liver cells can synthesize and store triglycerides. When the body needs an energy source, the liver initiates the breakdown of fatty acids from the triglyceride, which can be metabolized to energy.

Because the brain cannot utilize fatty acids to create energy, the liver causes the breakdown of the glycerol component of triglyceride into glucose.

High levels of triglycerides in the blood have been found to contribute to plaque formation, increasing the risk of cardiovascular disease. High levels of refined carbohydrates (above 60 percent of total energy intake) in the diet have been shown to lead to increased triglyceride levels in the blood.

Lipids and Diabetes

The interrelationship between blood lipid levels and elevated blood glucose levels is compelling. The American Diabetes Association describes a pattern of lipids (diabetic dyslipidemia) that is common to both pre-diabetics and diabetics. It consists of a moderate elevation of triglyceride levels, lower HDL cholesterol levels and small, dense LDL particles. This pattern of lipoproteins has been associated with insulin resistance and has been found even before the onset of diabetes.

Anyone who has a diagnosis of diabetes is at higher risk of cardiovascular disease. Anyone with a diagnosis of hyperlipidemia is also at increased risk of cardiovascular disease. The means to lower both blood lipids and blood glucose are a healthy diet and exercise.

Sources: American Heart Association and American Diabetes Association Clinical Diabetes Journals

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