Glucometers, continuous glucose monitors, and noninvasive glucose monitors are types of blood sugar monitors. At-home monitors allow someone with diabetes to easily monitor their blood sugar levels throughout the day.

People with diabetes must monitor and keep their blood sugar levels within the target range to manage their condition and reduce the risk of complications.

Blood sugar monitors can provide a quick, simple, and convenient way to check blood sugar levels.

People can then use this information to take appropriate actions, such as injecting insulin or consuming carbs to put their blood glucose into their target range.

This article discusses blood sugar monitors, who they are for, the different types, how to use them, and more.

Person staring into distance with blood sugar monitorShare on Pinterest
Dragoljub Bankovic/EyeEm/Getty Images

Blood sugar, or glucose, is the body’s main energy source. The body breaks down the food we eat into sugar. The blood carries sugar into the bloodstream to the body’s cells to supply energy.

Blood sugar level rises and falls throughout the day depending on factors such as:

Blood sugar monitors or glucose monitors are portable devices that analyze a person’s blood to check their blood sugar concentration.

Since blood sugar levels change throughout the day, doctors may require people to check their levels several times daily.

These at-home test devices can be invasive, noninvasive, or continuous. Glucose meters also vary in appearance, size, and features. Some may have accompanying apps, backlit screens, and USB ports, among other features.

People with the following conditions may need to monitor their blood glucose levels regularly:

A person’s doctor will determine how often they need to check their blood sugar levels. The frequency varies depending on the type of diabetes and medications a person is taking.

Frequency of use

Generally, a person checks their blood sugar levels:

  • upon waking up, before having any food or drink
  • before meals
  • 2 hours after a meal
  • before bed

An individual with type 1 diabetes does not produce enough insulin, which is why they must monitor their blood sugar levels closely.

They may need to test four or more times daily. They may need to test more often if they are ill, experience a change in their usual activities, or switch to a new medication.

Those with type 2 diabetes and gestational diabetes may only need to test two to four times daily. More frequent testing may be necessary depending on a person’s treatment.

A person with adult onset type 1 diabetes gradually loses their ability to produce insulin. Doctors will tell the individual how often to test, depending on the course of their condition.

There are three types of blood glucose monitors available on the market.

Blood glucose monitor or glucometer

Blood glucose monitors (BGMs) or glucometers measure a person’s blood sugar levels from a small sample, usually from a fingertip.

Glucometer kits come with lancets that people use to prick their fingers to obtain a blood sample. They run the test by inserting the strip into the monitor, which shows their current blood sugar level.

Continuous glucose monitor

A continuous glucose monitor (CGM) may benefit people who need to monitor their sugar levels more frequently to see trends and patterns. This includes individuals on intensive insulin therapy and those with widely variable blood sugar levels.

This device involves a tiny sensor under the skin, usually in the abdomen, upper arm, or thigh. This measures the blood sugar in the fluid between cells.

People can place some of these devices without help, while others require a doctor’s visit. A person still needs to regularly check their CGM and compare their readings with a BGM to ensure accuracy.

CGMs measure a person’s blood sugar levels every few minutes at regular intervals. Sensors come with transmitters, which send readings to a receiver.

People can clip or carry the monitor in their pockets or bags. Monitors can be stand-alone devices or can attach to a pump that delivers insulin depending on the person’s needs.

People can also use applications on their phones instead of receivers.

A 2020 systematic review suggests that CGM helps people with type 1 and type 2 diabetes maintain their blood sugar targets.

Noninvasive glucose monitor

These devices may be able to detect a person’s blood sugar levels without pricking their skin for a blood sample. These monitors use various mechanisms such as:

  • electrochemical
  • optical
  • microwave

A 2020 study compared the accuracy of a wrist-worn optical biosensor with an invasive clinical method of blood sugar monitoring.

The study authors suggest that wearable technology can produce results comparable to those of BGMs. However, more research is still necessary to test, validate, and approve these devices.

Additionally, the Food and Drug Administration (FDA) does not currently approve these devices.

How to use blood sugar monitors may depend on the type of monitor a person has. To use a monitoring kit, a person needs to follow the instructions in the kit’s manual.

However, the process generally works in similar ways. To use a blood sugar monitor:

  1. Prepare the test strip, monitor, and lancet.
  2. Make sure that the monitor is clean and working.
  3. Thoroughly wash and dry hands.
  4. Improve blood flow to the finger by warming the hand or massaging the finger.
  5. Turn on the glucometer and insert the test strip. Wait for the indicator to place the blood on the test strip. This step depends on the manufacturer’s instructions. Some monitors may need people to place the sample on the strip before putting the strip on the monitor.
  6. If using a finger prick device, put the finger in the lancet and secure the cap. Set the device by clicking or pulling the plunger.
  7. Prick the finger between the tip and the bottom of the fingernail. Do not prick too close to the nail.
  8. Place the drop on or on the side of the testing strip.
  9. Inspect the finger if it continues to bleed. Use a tissue or alcohol pad to stop bleeding.
  10. Wait for the monitor to show the reading. Record the reading.

People should never share blood sugar monitoring equipment with others.

Aside from regularly monitoring blood sugar levels, the following tips may help people manage them.

Exercise regularly

Regular exercise can stabilize blood sugar levels and increase insulin sensitivity.

However, a person needs to avoid exercising if ketones are in the urine. Additionally, it is advisable to avoid exercise if blood sugars are high, as physical activity may cause blood sugar levels to rise even higher.

Follow a diabetes meal plan

A person can keep their blood levels on track by sticking to a meal plan. This includes avoiding or counting carbs and choosing whole foods over highly processed foods such as white bread and artificial sweeteners.

Discover a 7-day diabetes meal plan.

Eat more fiber

Eating more fiber slows down sugar absorption and carb digestion. This can lead to a gradual increase in blood sugar levels instead of having sudden spikes.

High fiber intake may help people with type 1 diabetes manage their blood sugar.

A 2018 study also found that taking soluble fiber led to a significant reduction in metabolic syndrome profiles in people with a new diagnosis of type 2 diabetes.

Take medications as instructed

Adhering to prescribed medications can improve blood sugar management, help prevent complications, and reduce the frequency of hospitalization in people with type 2 diabetes.

A person also needs to be mindful of taking the right type and amount of medication at the time and frequency a doctor prescribes.

Reduce stress

When a person is stressed, their insulin levels fall. The body releases hormones that cause muscles and fat to become less sensitive to adrenaline. Moreover, adrenaline and glucagon levels rise, triggering the liver to release more glucose.

A 2021 study associates high anxiety, acute stress, and depression after the COVID-19 outbreak with the following factors among people with type 2 diabetes:

  • issues with glycemic levels
  • increased carb intake
  • snacking
  • diabetic complications

Maintain a moderate weight

A 2021 clinical trial suggests weight loss was the strongest predictor of type 2 diabetes remission at 12 months.

A balanced diet and regular exercise can help a person reach or maintain their ideal weight.

At-home monitoring devices can help people with diabetes track their blood sugar levels. These devices vary in size, appearance, and additional features.

Blood glucose monitors may be invasive, noninvasive, or continuous. A person can speak with a healthcare professional to understand the best monitor for them.

People who monitor blood sugar levels can take other steps to manage their blood sugar, such as regularly exercising, maintaining a moderate weight, and eating a balanced diet.