glycemia

Glycemia is the concentration of glucose in the blood. It reflects the balance between dietary intake, hepatic glucose production, and cellular uptake, regulated primarily by insulin and glucagon.

In healthy people, fasting plasma glucose is typically 70–99 mg/dL (3.9–5.5 mmol/L). After meals, glucose rises and is restored within hours by insulin-mediated uptake. Hypoglycemia is usually defined as a plasma glucose level below 70 mg/dL (3.9 mmol/L) and can cause symptoms such as tremor, sweating, and confusion.

Testing and targets include fasting plasma glucose, HbA1c, and the oral glucose tolerance test. Diabetes is diagnosed by fasting glucose ≥126 mg/dL (7.0 mmol/L) or HbA1c ≥6.5% or a 2-hour OGTT value ≥200 mg/dL; prediabetes corresponds to fasting 100–125 mg/dL or HbA1c 5.7–6.4%.

Chronic dysglycemia increases the risk of cardiovascular disease and microvascular complications, including retinopathy, nephropathy, and neuropathy. Management focuses on lifestyle modification, weight control, and glucose-lowering medications as appropriate, with ongoing monitoring through periodic HbA1c or continuous glucose monitoring in many settings.