What Is Glucose

Glucose is the main fuel your body uses for energy. Every cell in your body — your brain, muscles, heart, and organs — depends on a steady supply of glucose to function. Managing blood sugar means keeping that supply steady: not too high, not too low.

How It Works

When you eat, your digestive system breaks carbohydrates down into glucose, which enters your bloodstream. Your blood sugar level rises. In response, your pancreas releases a hormone called insulin. Insulin acts like a key that unlocks your body's cells, allowing glucose to enter and be used for energy or stored for later.

When you fast (during sleep, for example), your liver releases stored glucose to keep your brain and body fueled. Your pancreas then releases a small amount of insulin to manage that release.

In a healthy body, this system works automatically, keeping blood glucose in a narrow range around 80–100 mg/dL at rest.

What is mg/dL? It stands for milligrams per decilitre — it tells you how many milligrams of glucose are dissolved in every decilitre (100 ml) of your blood. A reading of 100 mg/dL means 100 milligrams of glucose per 100 ml of blood. Think of it like the concentration of sugar in a glass of water.

Your Target

For a person without diabetes, fasting glucose is typically 70–99 mg/dL and rarely exceeds 140 mg/dL even after meals. These are the ranges your body maintains naturally when everything is working well.

Why This Matters

When glucose stays too high for too long — even slightly above normal — it can damage blood vessels, nerves, and kidneys over time. The good news is that this damage develops slowly, and it is largely preventable. That is why tracking your glucose now, while you are in the prediabetic stage, is so valuable: you have the clearest window to make changes that matter.

What You Can Do

• Understanding your readings is the first step. A high reading after rice is not alarming — it is information about how your body responded to that meal.
• The goal is not to never see a high number. It is to understand what causes highs, reduce their frequency and size, and make consistent choices that keep your glucose in a healthy range most of the time.
• This app helps you connect the dots between what you eat, when you sleep, how much you move, and what your glucose does in response.

Based on: American Diabetes Association Standards of Care 2023; National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)