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No, Smart Watches and Rings Can’t Really Measure Blood Sugar

Smart watches and fitness trackers like Apple Watch, Oura Ring, and Fitbit cannot directly measure blood sugar levels, despite many users believing they can. We explain the limitations of optical glucose estimation methods and why they should not replace professional medical advice and direct blood glucose testing for diabetes management.
Smart watches and fitness trackers like Apple Watch, Oura Ring, and Fitbit cannot directly measure blood sugar levels, despite many users believing they can. We explain the limitations of optical glucose estimation methods and why they should not replace professional medical advice and direct blood glucose testing for diabetes management.


Smart health trackers like the Apple Watch, Oura Ring, and Fitbit more popular than ever. These wearable devices can track a variety of health metrics, from heart rate to sleep. But they can’t measure blood sugar and are not safe to use as blood glucose monitors.

Many users of these smart trackers believe they can directly measure blood sugar. After all, if they can track so many other stats, it seems logical that they may measure blood glucose, too.

However, this is not the case. Smart watches and rings do not actually measure blood sugar directly. Instead, they use indirect optical sensors to estimate glucose levels. This can be inaccurate and dangerous. Relying on these devices for diabetes management could lead to serious health consequences. Users should not depend on smart trackers to replace direct blood glucose testing.

Limitations of Smart Trackers That ‘Measure’ Blood Sugar

Smart health trackers like Apple Watch, Oura Ring, and Fitbit do not measure blood sugar levels directly. Instead, they use optical sensors to estimate glucose levels indirectly.

These optical sensors shine light into the skin and measure how that light reacts. Based on these light reactions, the devices attempt to calculate blood sugar levels. However, this method is not accurate.

There are a number of factors that can affect the accuracy of these optical glucose readings. Skin tone, tattoos, and even hand movements can all influence how light reacts with the skin. Thus leading to inaccurate glucose estimates. Environmental conditions like temperature and humidity can also play a role.

Ultimately, the method used by smart trackers is not as reliable as the testing done by traditional glucometers. Users should not depend on these devices to manage their diabetes or make important health decisions.

The US FDA Has Not Cleared Any Smart Watch or Ring To Measure Blood Sugar

The U.S. Food and Drug Administration (FDA) is warning consumers, patients, caregivers, and health care providers of risks related to using smartwatches or smart rings that claim to measure blood sugar without piercing the skin. These devices are different than smartwatch applications that display data from FDA-authorized blood glucose measuring devices that pierce the skin, like continuous glucose monitoring devices (CGMs).

The FDA has not authorized, cleared, or approved any smartwatch or smart ring that is intended to measure or estimate blood glucose values on its own.

US Food and Drug Administration

Smart Trackers Can’t Replace Blood Glucose Meters

Smart health trackers like watches and rings use optical sensors. Traditional blood glucose meters use a different technology to measure blood sugar levels. Glucometers use enzyme reactions to test the for glucose in a small blood samples.

This direct, enzymatic approach gives you an accurate and reliable reading. Blood glucose meters are intentionally built for the purpose of diabetes management. This means glucometers must ensure their measurements are clinically valid.

On the other hand, smart watches and rings are not approved medical devices. While they can provide helpful data, they are not intended for clinical management. Relying on consumer-grade devices for critical health decisions could lead to dangerous consequences.

How Does a Glucose Meter Measure Blood Sugar?

Using a Symptom Tracker Alongside Blood Sugar Monitoring

But you have all this health data in your smart tracker. What can you do with it that’s actually helpful? Pair your health data and glucose measurements together, and top it off with symptoms. This helps you see a big, holistic picture of your health. You can use a symptom tracker in tandem with a glucometer and smart health tracker.

A symptom tracker is a great complement to blood sugar monitoring. It allows you to:

Track Symptoms Alongside Blood Sugar

Checking your blood sugar with an approved meter is crucial for diabetes management. But tracking symptoms can also provide helpful insights.

See Patterns

Notice how your symptoms like fatigue or mood changes correlate with high or low blood sugar readings. This helps you understand your body’s signals.

Catch Issues Early

Logging concerning symptoms like blurred vision can alert you to check levels. Catching potential low or high blood sugar early prevents bigger problems.

Help Your Doctor

A log with readings and symptoms shows your doctor how diabetes affects you. They can then recommend personalized treatment based on your full experience.

Use All Tools Together

Smart watches can’t measure blood sugar accurately alone. But using one with a meter and symptom log gives a wider health picture. Combining direct data, symptoms, and activity helps manage diabetes more completely.

Tracking symptoms empowers you with deeper self-knowledge. Together with approved monitoring, it allows taking an active, informed role in your care.

Tips for Diabetes Management

Get Professional Guidance

For managing diabetes or blood sugar concerns, talk to a doctor or certified diabetes educator. These medical experts provide the right guidance.

Use an Approved Glucose Meter

Traditional glucometers remain the gold standard for accurate readings. They directly test your blood sample, not just estimate levels. Rely on a meter for making important health decisions about your diabetes, not a smart tracker.

Smart Trackers Have Limits

While devices like Apple Watch or Fitbit provide overall wellness data, they cannot replace professional medical advice or direct glucose testing. Their methods for measuring blood sugar have major limitations and inaccuracies.

Work Closely with Your Healthcare Team

If you have diabetes or worries about blood sugar, always consult your doctor for proper monitoring and management. Don’t depend on consumer trackers alone for a serious medical condition. Your healthcare provider knows what’s best for your specific needs.

Smart Watches and Rings Can’t Really Measure Blood Sugar

It’s important to understand that smart watches and fitness trackers cannot accurately measure blood sugar levels. They don’t test glucose directly.

Optical Blood Sugar Measures Are Unreliable

Instead of direct testing, these devices use optical sensors to estimate glucose indirectly. This method is far less accurate than traditional meters.

Many Factors Affect Accuracy

Things like skin tone, tattoos, and hand movements can throw off the optical readings from smart watches and rings. The results are unreliable.

Not Approved for Medical Use

Consumer smart trackers are not approved for diabetes monitoring and management. Don’t rely on them for critical health decisions.

Use Approved Meters and Guidance

If you have diabetes or blood sugar concerns, consult your doctor. They will guide you on using approved glucose meters for proper monitoring.

Smart trackers provide general wellness data, but have major limitations for measuring blood sugar accurately. Always follow medical advice for managing this condition.

Who we are

The Live Learn Innovate Foundation is a 501(c)3 nonprofit entity that empowers software users to regain control of their personally generated health data, gain intuitive insights about their social data, learn the impact of their environment on health, and build a foundation of data analytics that empowers research, academics, and innovation in economic development.

Use cases for this secure, private data aggregation method appear everywhere, expanding to family care, community growth, agricultural planning, and many more things still unseen. Help us keep going by getting involved today.

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