What is the most serious consequence of low blood sugar?

In the context of low blood sugar, often referred to as hypoglycemia, the most serious consequence is brain damage. The brain is highly sensitive to glucose levels; it relies on a steady supply of glucose to function properly. When blood sugar drops significantly, it can lead to a decreased supply of glucose to brain cells, resulting in neurological impairments. Prolonged hypoglycemia can cause brain cells to become damaged due to lack of energy, which can lead to irreversible changes.

While seizures, coma, and heart failure can occur in the setting of severe hypoglycemia, the most critical long-term consequence is brain damage. This highlights the importance of not only recognizing and treating low blood sugar promptly but also understanding that the brain's vulnerability makes hypoglycemia potentially life-threatening if untreated.