Which conditions may lead to decreased A1C levels?

Decreased A1C levels can occur due to several medical conditions and factors that affect hemoglobin and glucose metabolism.

Hemolytic anemia, such as seen in sickle cell disease, results in the breakdown of red blood cells at an accelerated rate. Since A1C testing measures the average blood glucose levels over a period of about three months by assessing glucose attached to hemoglobin, the shortened lifespan of red blood cells in hemolytic anemia leads to lower levels of A1C. This is because there are fewer red blood cells available for glucose to attach to, thus resulting in deceptively low A1C values.

Chronic renal failure can also lead to decreased A1C levels. In cases of chronic kidney disease, the kidneys are unable to effectively filter the blood, which can lead to disturbances in metabolism. These changes can affect blood glucose control and the lifespan of red blood cells, potentially leading to lower A1C measurements. Additionally, there may be altered manufacturing and destruction of red blood cells, which can further influence the accuracy of A1C levels.

Vitamin E supplementation has been reported to have antioxidant properties and may influence glucose metabolism and red blood cell stability. While it's a less direct effect compared to the two conditions previously mentioned, it