Accurate blood sugar testing is critical to staying safe and healthy with diabetes. It’s important to know which devices you can rely on to test your blood sugar. Many companies are creating new technologies that can test blood sugar without using a finger prick or test strips. Smartwatches are one option. But are they safe and effective for people with diabetes?

Here are four facts you should know about smartwatches for people with diabetes. We discuss whether they can actually measure blood sugar, what the U.S. Food and Drug Administration (FDA) says about them, and how accurate they are.

1. Blood Sugar Smartwatches Are Different From Smartwatches That Are Compatible With Glucometers

There are two different types of watches to be aware of. First, there are smartwatches that claim to measure blood sugar levels on their own, without piercing the skin. There are also smartwatches that are compatible with glucose monitors. With this device, a glucometer or continuous glucose monitor (CGM) tests your blood sugar levels and the watch displays the reading so you can easily check it from your wrist.

Smartwatches That Claim To Measure Blood Sugar

Blood sugar smartwatches are those that claim to measure your blood sugar without piercing the skin. The technology these smartwatches use varies, including:

• Optical — Shines light on the skin, which gets absorbed by glucose
• Electromagnetic — Stimulates the skin and blood vessels around the watch sensor and looks to see how glucose reacts
• Microwave — Sends microwaves into the skin and blood vessels and sees how much is reflected back by glucose
• Electrochemical — Detects glucose in bodily fluids other than blood (like sweat), which means it isn’t testing blood glucose specifically

These are different ways scientists and companies are trying to measure blood sugar without needing to poke the skin. These technologies may seem more convenient and less painful, but their safety and effectiveness for blood sugar management are still being studied.

Smartwatches Compatible With CGMs

Pairing smartwatches with CGMs can be an accurate and convenient way to watch your blood sugar levels. Many companies that make CGMs have apps that can be installed on a smartwatch so that you can check the blood sugar readings from the CGM on your watch.

Here are some examples of smartwatches that can be paired with certain CGMs to monitor your blood sugar:

• Fitbit
• Garmin watches
• Apple watches
• Samsung watches
• K-Watch glucose device

Connecting your CGM to a smartwatch means you can get blood sugar readings in real time throughout the day. This can help you make decisions to keep your blood sugar in check.

You may still need to have your smartphone or device that has the CGM app close to you in order to get blood sugar data on your smartwatch. To get readings from the Dexcom G7 sensor, for example, you need to have your smartphone with the app nearby.

2. The FDA Has Not Approved Smartwatches That Measure Blood Sugar on Their Own

In February 2024, the FDA issued a statement warning people not to use smartwatches to measure their blood sugar because they may provide inaccurate readings. This can be especially dangerous for people with diabetes who rely on blood sugar monitoring for their health and treatments.

The FDA stated that these types of devices haven’t been reviewed for safety and accuracy. This applies to all smartwatches that claim to measure blood sugar without piercing the skin. This doesn’t apply to smartwatches that connect to CGMs, which do provide an accurate reading and are monitored by the FDA.

The FDA is trying to make sure that smartwatches claiming to check blood sugar without using a needle aren’t sold to people if they aren’t approved. Since blood glucose smartwatches aren’t approved or cleared by the FDA yet, using FDA-approved glucometers or CGMs is the safest option for people with diabetes.

In a discussion about the Suga Pro smartwatch, one DiabetesTeam member said they were curious how it would compare to their CGM but that it might not be for people with diabetes: “I would be interested just to see what it can do because I could compare it to my Libre2 sensor, but I expect that it would be almost a ‘novelty’ for nondiabetics and not a serious blood sugar monitor.”

3. The Accuracy of Blood Sugar Smartwatches Isn’t Guaranteed

Not only have blood sugar smartwatches not been proven safe and effective by the FDA, but they also haven’t met the FDA’s accuracy requirements for over-the-counter blood sugar monitors.

One study tested a smartwatch that aimed to measure glucose through the skin from an electrochemical sensor on the wristband. The results showed that it accurately measured blood sugar about 84 percent of the time. This was a small study of 23 people, only 13 of whom had diabetes.

GWave sensors, which can be put into a wearable device like a watch, have also been studied for their accuracy. Testing of two early versions of GWave showed that it’s accurate 98 percent of the time. However, the studies were small and didn’t include people with diabetes.

Another study looked at the accuracy of InCheck, a device that uses a sensor to measure blood sugar from your finger. There is no finger prick. Data from over one thousand people with type 2 diabetes who used InCheck showed that the blood sugar readings met FDA accuracy requirements about 19 percent of the time.

So far, we know that the accuracy of these devices varies greatly, and no device is as accurate as a glucometer. More research is needed to figure out if and how these new technologies can be made safe and reliable for people with diabetes.

4. Smartwatches May Help With Other Types of Diabetes Management

Getting regular exercise is an important part of diabetes management. Smartwatches can help you meet your physical activity goals. Many smartwatches allow you to track different kinds of physical activity, such as walking, hiking, or strengthening.

Smartwatches can also accurately monitor your heart rate, both during exercise and at rest. Some smartwatches can also track your sleep patterns and measure your sleep quality. Seeing these health data can help you make informed decisions to improve your health and track progress over time.

The Importance of Accurate Blood Sugar Readings

Inaccurate readings from blood sugar smartwatches can be harmful to your health. Accurate readings are key to proper blood sugar management. If the smartwatch says your blood sugar is higher than it actually is, for example, you might take more insulin than your body needs. Taking too much insulin or other diabetes medications can lead to dangerously low glucose.

One DiabetesTeam member emphasized the importance of accurate blood sugar readings and advised against a blood sugar smartwatch: “They are not accurate, and it is just an easy way to get yourself in trouble. Stick with the blood sticks. Remember, if it sounds easy or too good to be true, it should be a hard pass when the device is supposed to help you make life decisions.”

Talk with a healthcare provider about how a smartwatch can help you manage your diabetes. The provider may be able to recommend smartwatches or apps to pair with your CGM. They may also offer other ways a smartwatch can support you with your diabetes care plan and overall health goals.

Talk With Others Who Understand

DiabetesTeam is the social network for people with diabetes and their loved ones. On DiabetesTeam, members come together to ask questions, give advice, and share their stories with others who understand life with diabetes.

Do you use a smartwatch to help monitor blood sugar? Does your device help you with daily diabetes management? Share your comments below, or start a conversation by posting on your Activities page.