What Are Normal Blood Sugar Levels?

Diabetes mellitus, or diabetes, is a disease that is, unfortunately, becoming more well-known.

The incidence of diabetes is increasing; according to the World Health Organization (WHO), the number of people with diabetes has risen from 108 million people in 1980 to 422 million in 2014.

Diabetes presents in two different ways; type 1 diabetes and type 2 diabetes. Type 1 diabetes is an autoimmune disease where the pancreas loses its ability to produce the hormone insulin, which helps lower blood sugar to keep it in a healthy range.

People with type 1 diabetes are known as “insulin-dependent” because they must inject insulin in order to live a healthy life.

Type 2 diabetes is linked to insulin resistance and is more likely to be passed along genetically, and can also occur due to lifestyle factors.

People with type 2 diabetes don’t necessarily need to be on insulin in order to survive, unlike people with type 1 diabetes. Risk factors for type 2 diabetes include age, ethnicity, family history, and lifestyle habits such as activity level.

People with and without diabetes are often curious to know what normal blood sugars are, why healthy blood sugar levels are important, how to test blood sugar and how to keep blood sugars in the normal range.

Normal range for blood sugar

Blood glucose, or blood sugar, is something necessary for survival in all mammals. Sugar is our body’s primary source of fuel.

The hormone insulin is required to help the sugar enter our cells, where it’s used as energy. Blood sugar levels are reported in milligrams per deciliter, or mg/dL.

There are different ranges of blood sugar considered normal; fasting and postprandial. Fasting blood sugar is our blood sugar level when we haven’t eaten for at least eight hours. People usually check their fasting glucose in the morning after waking. A normal fasting blood sugar is below 100 mg/dL.

Postprandial blood sugar refers to the blood glucose level after eating. Postprandial blood sugars are usually checked within 2 hours of starting a meal. Normal postprandial blood sugar should be less than 140 mg/dL.

Another way to measure blood sugar is by using a hemoglobin A1c test. This test measures the average blood sugar over the past three months. The A1c works by assessing the percentage of red blood cells that were attached to a sugar molecule. A normal hemoglobin A1c is less than 5.7%. The A1c is a good indicator of long-term blood sugar because it’s an average over several months.

Some women develop gestational diabetes (GDM) during pregnancy without having diabetes already. Some women develop insulin resistance during pregnancy due to hormonal changes.

It’s imperative to control blood sugar levels during pregnancy for the health and wellbeing of the mother and baby. Gestational diabetes often goes away after pregnancy, but having GDM does increase the risk of developing diabetes later.

What is considered too high for blood sugar?

Fasting blood sugar is considered borderline high when it’s between 100-125 mg/dL. People with borderline high fasting blood sugar may be considered to have prediabetes. Prediabetes is a condition where blood sugar levels are high, often due to insulin resistance.

Fasting blood sugar in gestational diabetes should be less than 95 mg/dL. The goal for GDM is more strict because of the risks of high blood sugar for the mother and baby.

Having prediabetes is a significant risk factor for eventually developing type 2 diabetes. In fact, the U.S. Centers for Disease Control (CDC) estimates that up to 30% of people with prediabetes will develop type 2 diabetes within five years of their prediabetes diagnosis.

Postprandial blood sugar is considered high when it’s above 140 mg/dL within two hours of starting a meal. For gestational diabetes, postprandial blood sugar is high when it’s above 120 mg/dL within two hours of starting a meal.

Hemoglobin A1c is considered borderline high (prediabetes) when it’s 5.7%-6.4%. The A1c is a more accurate way of diagnosing prediabetes because it’s over a longer period of time than just one fasting blood sugar test.

Not everyone will have symptoms of high blood sugar. Symptoms often occur once blood sugars have reached the point of a diabetes diagnosis.

Common symptoms of diabetes include unintentional weight loss, increased hunger, and thirst and frequent urination.

What is considered too low for blood sugar?

Low blood sugar is also referred to as hypoglycemia. Low blood sugar is below 70 mg/dL. Having low blood sugar is dangerous and can even lead to coma and death if left untreated. Some symptoms of low blood sugar include feeling dizzy or shaky, being hungry, sweating, and fainting.

How to check your blood sugar level

If you don’t already have diabetes, you will most likely have your blood sugar checked at your healthcare provider’s office. Many health insurance companies cover the cost of blood sugar testing as a part of an annual preventive health visit.

Your blood sugar will likely be checked using a venous blood draw, which is when a vial of blood is collected and sent to be analyzed. A venous blood draw is necessary to check hemoglobin A1c, as well.

The test will most likely be done fasting unless your healthcare provider instructs you otherwise. The A1c test does not require fasting and is often done during preventive visits as a diabetes screening tool.

Blood sugar levels can also be tested with instant results using a point of care, or POC, glucose test. This test is done using a handheld glucometer and fingerstick glucose; a small needle will pierce the skin of the finger to analyze a small drop of blood for its glucose content.

If a healthcare provider is very concerned that a person may have undiagnosed diabetes, they may order a POC glucose to discuss the results with their patients that same day.

If you have diabetes, you can check your blood sugar multiple times per day using a home glucometer kit. A healthcare provider prescribes these kits, and insurance usually covers the cost for people with a diagnosis of diabetes.

Glucometers provide blood glucose results within a few seconds of testing in the form of mg/dL. Hemoglobin A1c tests cannot accurately be tested at home, though there are some home kits marketed for this purpose.

How often should you get your blood sugar checked?

If you already have diabetes, the American Diabetes Association recommends checking your hemoglobin A1c checked every 3-6 months, depending on your blood sugar control.

How often to check to fast and postprandial blood sugars depends on the medications you take, as well as other aspects of your diabetes self-management plan.

If you have risk factors for diabetes, you should get your blood sugar screened every three years.

Some risk factors for developing type 2 diabetes include:

• Higher body weight primarily increased fat around the abdomen
  
  
• Inactivity
  
  
• Family history
  
  
• Race (African Americans, Hispanics, Native Americans, and Asian Americans are at higher risk)
  
  
• Being 45 years or older
  
  
• History of gestational diabetes during pregnancy
  
  
• Polycystic ovary syndrome in women
  
  
• High blood pressure
  
  
• Low HDL (good cholesterol) levels and/or high blood triglycerides

What steps can you take to correct high or low blood sugar?

If blood sugar is borderline high, such as the case with prediabetes, lifestyle changes are the only way to bring blood sugars down to a healthy level without medication.

Getting at least 30 minutes of physical activity most days of the week and making healthy eating choices are some of the best lifestyle habits to help improve insulin resistance and reverse prediabetes.

When blood sugar is high enough for a diabetes diagnosis, then an individualized plan should be made between the patient and their healthcare provider. Some people prefer to try lifestyle modifications before starting medications.

If blood sugar is dangerously high, some healthcare providers recommend starting medications immediately to reduce the risk of life-threatening complications.

A complication of very high blood sugar in type 1 diabetes is diabetic ketoacidosis (DKA), which is an emergency and should be treated promptly by a medical team.

If blood sugar is running higher than usual for a prolonged period of time, it’s best to visit with your regular healthcare provider.

Medications can be adjusted in order to achieve target blood sugar levels if current medications aren’t doing enough. It’s also vital to address chronically high blood sugar, as it can be a sign of something more serious, like an infection.

If blood sugar is below 70 mg/dL, the recommended treatment is to eat a portion of food or drink something containing 15 grams of carbohydrates. Sugary drinks and hard candies are preferred as they turn into sugar quickly.

You don’t need much juice to get to 15 grams of carbohydrates; about one-half cup is enough. After taking some carbohydrates, recheck blood sugar in 15 minutes. If it’s still below 70 mg/dL, repeat the treatment and retest blood sugar in another 15 minutes.

Importance of normal blood sugar

There are several things you can do to help lower blood sugar. Depending on the type and severity of a person’s diabetes, lifestyle modifications aren’t always enough to control blood sugar.

If this is the case, it doesn’t mean that the person isn’t doing a good enough job to control their blood sugar. It means that the pancreas isn’t making enough insulin, and the body needs some help in the form of medications such as injectable insulin.

Some lifestyle tips to help lower blood sugar include:

• Drinking calorie-free beverages such as water, unsweetened teas, etc. and avoiding sugary drinks such as soda, fruit juice, and sweetened coffee drinks
  
  
• Getting at least 30 minutes of moderate to vigorous exercise most days of the week
  
  
• Engaging in weight or resistance training once or twice per week
  
  
• Getting adequate sleep (sleep deprivation has been linked to higher blood sugar)
  
  
• Eat balanced meals and snacks, similar to the plate method
  
  
• Eat-in response to hunger and fullness cues, not based on what time it is
  
  
• Read food labels to identify added sugars in foods and drinks
  
  
• Check your blood sugar regularly; this can help you identify what is or isn’t working to help manage your diabetes

Why is normal blood sugar important?

Having chronically high blood sugar is hard on the entire body. It can cause many irreversible diabetes complications, including heart disease, neuropathy, kidney disease, retinopathy, and poorly healing wounds leading to amputations.

• Heart health: High blood sugar causes hardening of the arteries called atherosclerosis, which is a risk factor for developing cardiovascular disease (heart disease). If an artery becomes too narrow, it can become blocked, which results in a heart attack or stroke, depending on where the blockage occurs.
  
  

• Diabetes and insulin resistance: is also linked with dyslipidemia or abnormal cholesterol levels. Having high levels of LDL (bad) cholesterol and low levels of HDL (good) cholesterol increase the risk of heart disease.
  
  

• High blood pressure: People with diabetes are also more likely to have high blood pressure, which is another risk factor for heart disease.
  
  

• Kidney health: High blood sugar damages the vessels in the kidneys, which are responsible for removing waste from our blood and help to control blood pressure. If diabetes isn’t controlled, chronic kidney disease is more likely to occur. Chronic kidney disease can progress to the point of needing dialysis or a kidney transplant.
  
  

• Neuropathy and retinopathy: High blood sugar can cause nerve damage, known as neuropathy. Many people experience this in the form of peripheral neuropathy. Peripheral neuropathy causes pain as well as numbness and tingling of the extremities. Diabetes can also damage the blood vessels in the eyes, which leads to retinopathy. Retinopathy can potentially lead to loss of vision.
  
  

• Wound healing: High blood sugar impairs the body’s ability to heal itself. When wounds don’t heal quickly, there is a higher chance of infection. The chances of wound complications are even higher if the person also has neuropathy because they can’t feel the wound, and it may go untreated for a long time.
  
  

• Amputation: If limbs are severely damaged from a poorly healing wound, it may need to be amputated. In fact, diabetes is thought to be the leading cause of leg amputations worldwide.

How accurate is a fasting blood sugar test?

In general, fasting blood sugar tests are considered very accurate. These tests aren’t affected by diet because the individual should have abstained from eating for at least eight hours prior to the test.

A fasting blood sugar test wouldn’t be accurate if the person had something to eat or drink (other than water) within the previous eight hours. Illness and stress can also cause high blood sugar in some people, so that could alter the effectiveness of the test.

User error could also impact the accuracy of the test, but if it’s performed in an accredited laboratory, the user error rate should be low.

Because of normal day-to-day fluctuations in blood sugar, many healthcare providers prefer using the hemoglobin A1c test to get a bigger picture of blood sugar trends.

Best supplements for maintaining blood sugar

For people not requiring medications to control their blood sugar, supplements may be beneficial.

It’s important to choose a reputable supplement brand and to realize that not everyone will experience the same outcomes taking supplements.

• Cinnamon is a more well-known supplement for its potential blood sugar-lowering effects. Some studies have found that cinnamon can help lower fasting blood sugar, as well as help promote normal cholesterol and triglyceride levels.
  
  

• Aloe vera may help to lower blood sugar and hemoglobin A1c, as well as improve cholesterol levels. There are few studies on this topic, though.
  
  

• Chromium is a mineral that is beneficial for insulin action and carbohydrate metabolism. People with diabetes often have lower levels of chromium than people without diabetes. Supplements containing chromium picolinate have been found to improve blood sugar control.
  
  

• Fenugreek can help lower blood sugar by increasing insulin levels. Another benefit is that it can also help lower cholesterol levels.

While these supplements may help improve blood sugar and insulin sensitivity, they shouldn’t be used as a sole method to control diabetes symptoms. Diabetes symptoms occur when blood sugars are very high, which warrants a visit with a healthcare provider.

Conclusion

Normal blood sugar levels are important for promoting overall health and wellbeing. In the case of prediabetes and diabetes, blood sugar levels are considered higher than the normal range.

High blood sugar over a long period of time can lead to unwanted complications, and low blood sugar also poses a health risk.

Blood sugar can be tested in a laboratory per your healthcare provider. If you already have diabetes, you can check blood sugar levels at home regularly using a glucometer.

You can promote healthy blood sugar levels by being physically active and eating a mindful, balanced diet. Other aspects of a diabetes care plan include taking diabetes medications and checking blood sugar regularly and have a blood sugar target.

Supplements may also be used to promote healthy blood sugar, but they shouldn’t be used in place of the recommendations of your healthcare provider.

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