Understanding Blood Sugar (Glucose)
Blood sugar, or glucose, is the main sugar in your bloodstream and the primary energy source for your body’s cells. Your brain, muscles, and organs rely on glucose to function. But because glucose levels must be carefully controlled, your body has an intricate system to regulate it.
How Blood Sugar Gets Into Your Body
From the food you eat: Carbohydrates—like bread, rice, fruit, and vegetables—are broken down into glucose during digestion and absorbed into your bloodstream.
From stored energy: Your liver can release stored glucose (called glycogen) into the blood when you haven’t eaten, such as overnight or between meals.
How Your Body Controls Blood Sugar
The body keeps blood sugar in a tight range (usually 70–100 mg/dL fasting). This regulation involves two main hormones:
Insulin – Produced by the pancreas when blood sugar rises (like after a meal). Insulin helps cells take in glucose to use for energy or store as glycogen in the liver and muscles.
Glucagon – Produced by the pancreas when blood sugar drops (like during fasting or exercise). Glucagon signals the liver to release stored glucose to keep your body fueled.
Other hormones like cortisol, adrenaline, and growth hormone also affect blood sugar, especially during stress or sleep deprivation.
What Happens When Blood Sugar Goes Too High or Low
High blood sugar (hyperglycemia): Can occur after eating too much sugar or if insulin isn’t working properly (as in diabetes). Chronic high blood sugar can damage blood vessels, nerves, and organs.
Low blood sugar (hypoglycemia): Can occur if you skip meals, exercise intensely, or your insulin/glucose balance is off. Symptoms include shakiness, sweating, anxiety, and in severe cases, confusion or fainting.
Why Balance Matters
Stable blood sugar keeps your energy steady, protects your organs, supports brain function, and regulates hunger and mood. Eating balanced meals, sleeping well, managing stress, and staying active all help maintain healthy glucose levels.