Blood sugar, or blood glucose, is one of the most important indicators of your overall health. Whether you’ve heard the terms “blood sugar spike,” “prediabetes,” or “insulin resistance,” understanding how blood sugar works and why it's monitored by your primary care provider (PCP) is key to preventing long-term health complications.
What Is Blood Sugar?
Blood sugar (or blood glucose) is the amount of sugar (glucose) present in your bloodstream. Glucose is your body’s main source of energy and comes from the food you eat—primarily from carbohydrates. Your brain, muscles, and organs all rely on a steady supply of glucose to function properly.
The Body Turns Food Into Glucose
When you eat, your digestive system breaks down carbohydrates—found in foods like bread, rice, fruits, and sweets—into glucose. This glucose is absorbed into the bloodstream, causing your blood sugar level to rise.
In response, your pancreas releases insulin, a hormone that acts like a key to help glucose move from your bloodstream into your cells, where it’s used for energy. Any excess glucose that’s not immediately needed is stored in the liver or muscles for later use—or converted to fat.
What Happens When Blood Sugar Is Too High?
If your body doesn’t produce enough insulin—or doesn’t respond to it properly—glucose builds up in your bloodstream instead of fueling your cells. This condition is known as hyperglycemia, or high blood sugar.
Long-term high blood sugar can:
- Damage blood vessels and nerves
- Lead to vision problems or blindness
- Increase the risk of heart disease and stroke
- Impair kidney function
- Cause slow wound healing and increased infection risk
Over time, consistently high blood sugar can lead to prediabetes and eventually type 2 diabetes, both of which increase the risk of serious, long-term health complications if left unmanaged.
What Is Prediabetes?
Prediabetes is a condition where your blood sugar levels are higher than normal but not high enough to be diagnosed as diabetes. It is a warning sign that your body is starting to struggle with managing glucose efficiently.
Many people with prediabetes don’t have symptoms, which is why regular screening is essential. Early lifestyle changes—such as improved nutrition, increased physical activity, and weight loss—can often reverse prediabetes and prevent the development of type 2 diabetes.
How Does the Body React to Low Blood Sugar?
Low blood sugar, or hypoglycemia, occurs when blood glucose drops below the normal range. This can happen in people with diabetes who take insulin or other medications, or in those who skip meals or exercise heavily without proper nutrition.
Symptoms of low blood sugar include:
- Shakiness or dizziness
- Sweating
- Rapid heartbeat
- Irritability or confusion
- Fatigue
- In severe cases, fainting or seizures
Managing low blood sugar typically involves eating quick-acting carbohydrates like fruit juice or glucose tablets to bring levels back up quickly.
What Do Blood Sugar Spikes Do to the Body?
A blood sugar spike happens when glucose levels rise quickly after eating, especially after high-carb or sugary meals. Frequent spikes can:
- Stress the pancreas to produce more insulin
- Lead to insulin resistance over time
- Cause energy crashes that make you feel tired or irritable
- Trigger inflammation and damage blood vessels
Over time, repeated blood sugar spikes increase the risk of developing prediabetes, type 2 diabetes, and cardiovascular disease.
