Facts About Hypoglycemia

A person's blood glucose (sugar) levels vary throughout the day. Hypoglycemia (low blood sugar) usually starts out as mild and can easily be treated by consuming a small amount of food or beverage high in glucose. However, blood glucose levels can become severely low if left untreated, which can be very dangerous.

This article highlights important facts and statistics you should know about hypoglycemia, including how common it is, who is more at risk, causes, early detection, prevention, and mortality.

Person taking finger prick blood sample to test blood sugar for hypoglycemia

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Hypoglycemia Overview

Hypoglycemia is low blood glucose levels. Generally, when blood glucose levels are below 70 milligrams per deciliter (mg/dL), it is called hypoglycemia. Hypoglycemia typically occurs in people with diabetes, though people without diabetes can experience hypoglycemia too.

How Common Is Hypoglycemia?

Hypoglycemia is common among people with diabetes. It is particularly seen in people with type 1 diabetes or type 2 diabetes who take insulin or other specific diabetes medications.

Global research has shown that 4 in 5 people with type 1 diabetes and almost half of people with type 2 diabetes who take insulin reported experiencing hypoglycemia at least once over a period of four weeks.

Severe hypoglycemia, or when your blood glucose levels are so low that you need someone to help you treat it, is not as common. About 2 in 100 American adults with diabetes who take insulin or other specific diabetes medications that help increase insulin in the blood, might experience severe hypoglycemia yearly.

Nondiabetic hypoglycemia is a rare medical condition that occurs in people without diabetes.

Hypoglycemia by Ethnicity

A global study of 24 countries reported that the highest rates of hypoglycemia events were reported in Latin America for type 1 diabetes and Russia for type 2 diabetes.

In a study looking at trends of severe hypoglycemia in U.S. veterans from 2004 to 2015, researchers reported the rates of severe hypoglycemia declined over the years. The rates were much higher in Black veterans, but the gap between rates in Black and White veterans narrowed from a 34.7% difference in 2004 to a 13.2% difference in 2015.

A large cohort study looking at racial differences in diabetes management among children with type 1 diabetes found large gaps in insulin treatment methods and treatment outcomes between Black versus Hispanic and White children, even after adjusting for socioeconomic status.

In that study, diabetic ketoacidosis (a complication of diabetes and high blood sugar) or severe hypoglycemia were observed more in Black participants in the previous year than in White or Hispanic participants.

Hypoglycemia by Age and Sex

Older age can increase the risk of developing hypoglycemia. This may be due to several factors, including the higher rate of coexisting conditions such as kidney failure, malnutrition, cancer, and dementia.

Some studies have shown that hypoglycemia is more common in women. The reason women seem to be more prone to hypoglycemia is not well understood. However, some experts suggest it may be related to differences in hormones, body fat distribution, and slower glucose absorption compared to men.

Causes of Hypoglycemia and Risk Factors

Possible causes for hypoglycemia include:

What Are the Mortality Rates for Hypoglycemia?

Most studies investigating mortality rates related to hypoglycemia have found severe hypoglycemic events are stronger predictors of mortality than mild or moderate hypoglycemia.

For example, one study of adults with diabetes found that five years after reporting their frequency and severity of hypoglycemia, people who reported having experienced severe hypoglycemia had a 3.4-fold higher mortality than those who reported mild or no hypoglycemic events.

A large prospective cohort study looking at hospitalized people with and without diabetes found that hypoglycemia, regardless of insulin use, was also associated with higher short- and long-term mortality.

Some research has found a possible link between hypoglycemia and cardiovascular events. A prospective cohort study of people with diabetes, with a median follow-up of more than 15 years, found that people who experienced severe hypoglycemia had a higher risk of coronary heart disease, cardiovascular mortality, and overall mortality.

Prevention and Early Detection

Identifying hypoglycemia can help you prevent it from becoming too low. Though low blood glucose symptoms may vary from person to person, here are some signs and symptoms to watch out for:

The only way to know for sure if you are truly experiencing hypoglycemia is to check your blood glucose levels when possible. If you are experiencing hypoglycemia symptoms and cannot check your blood glucose level, treat it as if you do have hypoglycemia.

Hypoglycemia Unawareness

Some people do not notice or feel any symptoms of low blood sugar when they are experiencing hypoglycemia. This is called hypoglycemia unawareness. If you have hypoglycemia unawareness, you might need to check your blood glucose levels more often for low blood glucose and treat it, if needed.


Certain situations, such as driving or being physically active, can be especially dangerous if you are experiencing hypoglycemia—so it's important to check blood glucose levels beforehand.

Summary

Hypoglycemia refers to having low blood glucose levels. It is more common among people with diabetes, especially those who use insulin and other certain diabetes medications. Research suggests that Blacks are more likely to experience hypoglycemia than Whites.

In addition, older age is a risk factor for hypoglycemia. Women may be more likely than men to experience it. People who have experienced severe hypoglycemia seem to have an increased risk of mortality compared to those who have experienced mild or no hypoglycemia.

Knowing the potential causes of hypoglycemia and the signs and symptoms can help you prevent or identify early hypoglycemia. Having blood glucose testing supplies always on hand and knowing how to treat hypoglycemia can help prevent it from becoming too low.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Brittany Poulson, MDA, RDN, CD, CDCES
Brittany Poulson, MDA, RDN, CDCES, is a registered dietitian and certified diabetes care and education specialist.