Which substance accumulates and leads to acidosis in untreated diabetes mellitus?

Which substance accumulates and leads to acidosis in untreated diabetes mellitus?

• A. Ketones
• B. Glucose
• C. Lactic acid
• D. Glutamic acid

Answer: (A)

When insulin is deficient, fat breakdown speeds up, releasing fatty acids that the liver converts into ketone bodies. These ketone bodies—acetoacetate and beta-hydroxybutyrate—accumulate in the blood and are acidic, driving the metabolic acidosis seen in untreated diabetes (diabetic ketoacidosis). While glucose builds up due to lack of insulin, it does not cause the acidosis by itself. Lactic acid would cause lactic acidosis only with tissue hypoxia, and glutamic acid isn’t the culprit here. So the accumulating ketone bodies are what lead to the acidosis.

When insulin is deficient, fat breakdown speeds up, releasing fatty acids that the liver converts into ketone bodies. These ketone bodies—acetoacetate and beta-hydroxybutyrate—accumulate in the blood and are acidic, driving the metabolic acidosis seen in untreated diabetes (diabetic ketoacidosis). While glucose builds up due to lack of insulin, it does not cause the acidosis by itself. Lactic acid would cause lactic acidosis only with tissue hypoxia, and glutamic acid isn’t the culprit here. So the accumulating ketone bodies are what lead to the acidosis.