Why It's Important to Monitor Glucose Levels

For Those With Type 1 or Type 2 Diabetes

Regular glucose monitoring is important for people with type 1 or type 2 diabetes. Monitoring can help you and your healthcare team understand what affects your blood sugar levels. This information can be used to guide decisions about your diabetes care plan. Having the right care plan in place can help prevent or delay complications of diabetes.

This article looks at how glucose can affect your body, and what can cause your glucose levels to fluctuate. It also talks about how you can monitor your blood sugar and the best ways to manage blood sugar levels.

Woman at a table taking her blood sugar level with a pen

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Glucose Levels: What You Need to Know

Your blood sugar level is the amount of glucose in your blood. Glucose is the main sugar found in the bloodstream. It comes from the foods you eat and is your body's main source of energy.

The amount of glucose in your blood varies throughout the day. It changes depending on what and when you've eaten, and whether or not you've exercised. For example, levels rise after eating and fall after exercising.

The American Diabetes Association (ADA) has standard blood glucose recommendations for people living with diabetes. These ranges differ based on your age, how long you've had diabetes, and if you have any other health conditions.

  • Before meals: 80 to 130 mg/dL
  • One to two hours after meals: Below 180 mg/dL

When you have diabetes, your blood sugar can be either too low or too high. 

Hypoglycemia is low blood sugar. It is defined as a glucose level of less than 70 mg/dL or slightly higher.

High blood sugar, or hyperglycemia, is characterized by a glucose level of 100 to 125 mg/dL while fasting (not eating for at least eight hours). This is considered to be prediabetes. A person with a fasting blood glucose of higher than 125 mg/dL is said to have diabetes.

Insulin Regulation of Blood Sugar

When you digest your food, the carbohydrates are broken down into glucose. The stomach and small intestine absorb glucose and release it into the bloodstream. Your body can either use this glucose immediately or store it for later.

Insulin helps your body use and store glucose. When you have diabetes, your body doesn't make enough of this essential hormone or can't use it well. This causes the glucose to stay in the bloodstream.

Who Is Most at Risk?

People who have a family history of type 1 diabetes are more likely to develop this form of the disease. It is also more common in children, adolescents, and young adults.

Risk factors for type 1 diabetes are not as clear as those for type 2 diabetes. You're more likely to develop type 2 diabetes if you:

  • Have prediabetes
  • Are overweight
  • Are age 45 or older
  • Have a family history of diabetes
  • Are physically active less than three times a week
  • Have a history of gestational diabetes or gave birth to a baby weighing more than 9 pounds
  • Have a history of nonalcoholic fatty liver disease

Some ethnicities are also more at risk of type 2 diabetes. According to a 2017 ADA study, Black, Asian, and Hispanic populations in the U.S. are at higher risk of developing type 2 diabetes than White populations.

Why Glucose Levels Fluctuate

A number of factors can cause a person's blood sugar to go up or down.

Medications

Some medications can severely raise, or less often, lower blood glucose levels. These include:

These medications can cause insulin to become more or less sensitive, leading to blood sugar fluctuations.

Diabetes medications can also cause fluctuations in blood glucose levels. This may happen if you don't take enough medication or you take too much. It can also happen if the amount of carbohydrates you are eating or drinking is not balanced with the amount of insulin you inject.

It's vital to discuss any symptoms or concerns with your healthcare provider. Keep your medical team in the loop about the medications you're taking and any changes to the dosage.

Other Factors

Other factors that can contribute to high blood glucose include:

  • Too much food, such as a meal or snack with more carbohydrates than usual
  • Not being active
  • Not enough insulin or oral diabetes medications
  • Illness (your body releases hormones to fight the illness, and those hormones raise blood glucose levels)
  • Stress
  • Short- or long-term pain, such as pain from a sunburn
  • Menstrual periods
  • Dehydration

Factors that can lead to low blood sugar include:

Why Is It Important to Monitor Glucose Closely?

Keeping a close eye on your blood sugar helps you manage your diabetes. When your diabetes is well-managed, you are less likely to develop serious health problems.

When your blood sugar is too high for too long, you may develop a serious condition called diabetic ketoacidosis. When you have this condition, your body produces too many acids called ketones. Untreated, this can lead to a diabetic coma, a life-threatening condition that causes you to lose consciousness.

Very high blood sugar can also lead to diabetic hyperosmolar syndrome. With this condition, your blood becomes thick and syrupy and you may become severely dehydrated. This, too, can lead to diabetic coma.  

A diabetic coma may also develop when you are severely hypoglycemic.

Long-term, unmonitored (or poorly monitored) blood glucose can cause health problems like:

Glucose monitoring helps you identify what makes your levels fluctuate so you can avoid the things that negatively affect you. It also helps you catch high or low blood sugar early so you will be less likely to develop these dangerous conditions.

It's also important to log any changes in blood sugar levels so they can be shared with your healthcare providers. Your healthcare providers can use this information to develop your healthcare plan or make adjustments to your treatments.

How to Monitor Your Blood Glucose

There are two ways to measure blood sugar:

  • Blood sugar checks that you do yourself with a glucometer
  • The A1C test done in a lab or at your provider’s office, which tells you your average blood sugar level over the past two to three months

Home Blood Glucose Meter

Home blood sugar monitoring is important to keep track of daily fluctuations in your glucose levels. Most people with type 1 or 2 diabetes who take insulin should monitor their blood sugar levels regularly.

If you have type 1 diabetes, you may need to check your levels between 4 and 10 times a day. This usually means before meals and snacks, before and after exercise, before bed, and sometimes during the night. You may need to monitor your blood sugar levels more often if you are sick or have a change in your routine.

If you have type 2 diabetes, you may need to monitor your blood sugar less often depending on what type of insulin you take. This usually means testing before the first meal of the day, and sometimes before dinner or before bed.

People who are able to manage their diabetes without insulin may not have to test blood sugar every day. Make sure to discuss this with your healthcare provider.

A1C Test

If you have prediabetes or other risk factors, your healthcare provider may order an A1C test to screen for diabetes. Also known as the hemoglobin A1C or HbA1c test, this test estimates your average blood sugar levels over the past three months.

Because an A1C provides information about your blood glucose levels over time, it helps give your healthcare provider a picture of how well you've been managing your blood sugar. Most people with diabetes will have an A1C test at least two times a year.

Managing Glucose Levels

Many lifestyle factors can help you manage your blood sugar. This includes things like eating a healthy diet with plenty of fruits and vegetables, maintaining a healthy weight, and getting plenty of exercise. Other tips for managing your glucose levels include:

  • Eat at regular times, and don’t skip meals
  • Choose foods lower in calories, saturated fat, trans fat, sugar, and salt
  • Track your food, drink, and physical activity
  • Drink water instead of juice or soda
  • Limit alcoholic drinks
  • For a sweet treat, choose fruit
  • Control your food portions

Your healthcare team is a resource for information on natural treatments and medications. Be sure to discuss lifestyle and medication changes with them. Don't be afraid to ask questions if you have concerns or are struggling with how to live with diabetes.

Summary

Monitoring your glucose levels is a critical part of managing your diabetes. When you know how your blood sugar is affected by what you eat and your daily activities, you can help keep it from getting too high or too low.

Your glucose levels can be impacted by medications or even minor things like your activity levels, short-term illnesses, and what and how much you're eating. If your blood sugar gets too high or too low, it can cause dangerous short-term conditions that can lead to diabetic coma. In the long term, it can cause chronic health problems like heart or kidney disease.

Depending on what type of diabetes you have and how you are controlling it, you may need to test your glucose once a day or more than 10 times a day. Make sure to work closely with your healthcare team to develop a monitoring schedule that works best for you.

A Word From Verywell

Monitoring blood sugar is the most important part of managing diabetes. Unmonitored fluctuations can lead to hyperglycemia or hypoglycemia. These dangerously high or low levels can cause severe complications.

The symptoms and complications of high or low blood sugar are scary, but they are also avoidable. If you have concerns about your blood sugar levels, work with your healthcare team to monitor and make changes to your lifestyle or medications.

Frequently Asked Questions

  • How can you lower glucose levels?

    Lifestyle modifications such as getting regular exercise and following recommendations for diet can help with lowering glucose levels over time. Depending on the type and severity of diabetes, insulin or other medications may also be needed. If your blood sugar is above 240 mg/dL, check with your doctor.

  • What are normal glucose levels?

    A fasting blood sugar level of 99 mg/dL or lower is considered normal. Your blood sugar is tested after an overnight fast, meaning you don't eat until after the test is taken.

  • How does insulin regulate blood sugar levels?

    Insulin is a hormone that allows glucose to move from your blood into your cells. It also signals the liver to store blood sugar for later. Glucose can build up in your blood if your cells don't respond to the insulin or your body doesn't make enough insulin.

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11 Sources
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