Blood sugar, also known as blood glucose, refers to the level of sugar (glucose) circulating in your bloodstream, which serves as your body's primary source of energy; it primarily comes from the carbohydrates you consume in food, which are broken down into glucose and absorbed into the bloodstream during digestion; when blood sugar levels rise, the pancreas releases a hormone called insulin, which acts as a key to allow glucose to enter your cells and be used for energy; if your body doesn't produce enough insulin or doesn't utilize it effectively, blood sugar levels can become abnormally high, leading to a condition called diabetes; maintaining a healthy blood sugar level is crucial for overall health, and monitoring blood sugar levels through testing is particularly important for individuals with diabetes, as managing fluctuations can help prevent complications associated with the disease; factors that can affect blood sugar levels include diet, exercise, stress, and medications; when blood sugar drops too low, it can lead to hypoglycemia, characterized by symptoms like shakiness, sweating, and dizziness, which may require immediate intervention depending on severity.