Blood glucose level refers to the amount of sugar in your blood. Glucose in your blood comes from the foods — primarily carbohydrates — you eat, and is mediated by the hormone insulin, which is released by your pancreas.

Insulin enables the body to use glucose as fuel. Another hormone called glucagon, which stores excess glucose in the liver, allows that glucose to be released if your level falls too low.

Traditionally, blood glucose testing has been conducted primarily for detection of diabetes, which can damage the body years before symptoms occur.

Today, the American Diabetes Association recommends glucose testing begin at age 45, and is especially important for people in these risk groups:

• People who have prediabetes (insulin resistance)

• People who are overweight

• People who have a parent, sibling, or grandparent who developed diabetes

• People who have high cholesterol or triglycerides

• Women who had gestational diabetes when pregnant, or who gave birth to a baby larger than 9 pounds

• People who are physically active less than three times a week

• People who have nonalcoholic fatty liver disease

• People who are African American, Latino American, American Indian, or an Alaska Native (some Pacific Islanders and Asian Americans are also at higher risk)

• Women with polycystic ovary syndrome (PCOS)