The brain is the organ that is most affected by hypoglycemia (low blood sugar). The brain relies on a constant supply of glucose (sugar) to function properly, and when blood sugar levels drop too low, the brain is one of the first organs to be affected. This can cause a range of symptoms, including confusion, irritability, dizziness, headaches, seizures, and even loss of consciousness. In severe cases, hypoglycemia can lead to permanent brain damage or death. It is important to monitor blood sugar levels and seek immediate medical attention if hypoglycemia is suspected, especially in individuals with diabetes or other medical conditions that can affect blood sugar levels.