Hypoglycemia

Hypoglycemia happens when the level of sugar (glucose) in your blood drops below the range that’s healthy for you. It’s also called low blood sugar or low blood glucose. Hypoglycemia is common in people with diabetes, especially Type 1 diabetes.

For most people with diabetes, hypoglycemia is when your blood sugar level is below 70 milligrams per deciliter (mg/dL) or 3.9 millimoles per liter (mmol/L).

For most people without diabetes, hypoglycemia is when your blood sugar level is below 55 mg/dL or 3.1 mmol/L.

Hypoglycemia requires immediate treatment by eating or drinking sugar/carbohydrates. Severe hypoglycemia can be life-threatening and requires treatment with emergency glucagon and/or medical intervention.

What is blood sugar?

Glucose (sugar) mainly comes from carbohydrates in the food and drinks you consume. It’s your body’s main source of energy. Your blood carries glucose to all of your body’s cells to use for energy. Glucose is very important because it’s the primary source of energy for your brain.

If you don’t have diabetes, several bodily processes naturally help keep your blood glucose in a healthy range. Insulin, a hormone your pancreas makes, is the most significant contributor to maintaining healthy blood sugar. Glucagon is another important hormone in this process.

People who have diabetes must use medication, like oral diabetes medications or synthetic insulin, and/or lifestyle changes to help keep their blood sugar levels in range.

Low blood sugar often happens due to excess insulin — whether your body naturally makes too much or you inject too much synthetic insulin. Other hormonal and metabolic issues can also lead to low blood sugar.

If your blood sugar drops below the healthy range, it causes certain symptoms like shakiness and a faster heartbeat and can be life-threatening if it goes too low. This is because your brain needs a continuous supply of glucose to function properly. Without enough glucose, your brain can’t function.

How common is hypoglycemia?

Hypoglycemia is common in people with diabetes, especially people who take insulin to manage the condition.

One study found that 4 in 5 people with Type 1 diabetes and nearly half of all people with Type 2 diabetes who take insulin reported a low blood sugar episode at least once over a four-week period.

People with Type 2 diabetes who take meglitinide or sulfonylurea oral diabetes medications are also at an increased risk for low blood sugar.

You can experience hypoglycemia without having diabetes, but it’s uncommon.