What Is Diabetes?

May 2004

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To understand what diabetes is, it’s necessary to understand how the body normally works when food is eaten. Food is made of three parts: protein, carbohydrate, and fat.

When food is digested, the protein is broken down into amino acids; the fat is broken down into fatty acids; and the carbohydrate is broken down into glucose. It is easy to see, then, that most of the glucose (sugar) in your blood comes from the carbohydrate in foods.

Normally when carbohydrate is eaten and digested, blood glucose rises, which causes insulin to be secreted from the pancreas. The insulin is needed for glucose to move into cells.

When insulin responds to a higher blood glucose, the glucose enters the cells where it is either used as energy or stored as glycogen or converted for long-term storage as adipose (body fat).

Diabetes is the medical word used when someone either doesn’t have any insulin or when the insulin they have isn’t effective. When someone doesn’t have any insulin, it is called type 1 diabetes. When the insulin is not effective, it is called type 2 diabetes. In both cases, the blood glucose stays high unless medication is given or the diet is changed.

Karen Chapman-Novakofski, RD, LD, PhD