Samsung and Apple are both expected to come this year with a smartwatch that measures your blood sugar. This should make life a lot easier for people with diabetes. But what kind of sensor is it, how does it work and above all: how reliable are the measurements?
Measure your glucose levels without a needle
Scientists have been working on various lighting techniques that help measure the glucose levels in your blood for years. Needles should therefore become redundant in the future. Smartwatches already measure the saturation values in your blood by means of similar light technologies. Many wearables have been measuring your heart rate for years. A smartwatch that measures your blood sugar sounds like a logical next step.
However, developing a compact blood sugar sensor is not easy. The technique reportedly being investigated by Samsung and Apple is called Raman spectroscopy. It’s promising but complicated. Researchers have not yet managed to achieve the desired reliability in a compact and affordable device.
How does this non-invasive way of measuring blood sugar work?
Scientists worldwide research Raman spectroscopy. The Diabetes Fund and TNO are also conducting research on Dutch soil. The sugar molecules in the blood reflect monochromatic light, which is shone through a bright light on the forearm. The glucose molecules in the blood reflect some of this light, which is then converted into a blood sugar value.
The results of the studies are generally reliable. They differ little from the glucose values determined by injection. One problem: the measuring devices are still huge and expensive. So the question is how manufacturers are going to cram Raman spectroscopy into their affordable smartwatches – and whether the technology will still be just as reliable.
Reliability has long been a topic of discussion
It is not the first time that the reliability of such sensors in wearables has raised doubts. In 2020, Apple announced the Apple Watch Series 6, which can measure the saturation level in your blood. The new OnePlus Watch and Galaxy Watch 3 from Samsung also have a so-called SpO2 sensor.
The SpO2 sensors in these smartwatches appear not to be suitable for medical use because the results are not always reliable. You may therefore wonder to what extent such a sensor is of any use at all.
Dangerous and misleading
Manufacturers release wearables with new features and sensors every year. However, according to critics, these features are ahead of the technology, making them not reliable enough. That can be dangerous and misleading. Manufacturers state neatly that the SpO2 sensor in their wearables should not be used for medical use, but in the very fine print.
It remains to be seen to what extent blood sugar meters can be used with confidence in future smartwatches. Both Samsung and Apple watches are expected to be announced in the third quarter of 2021. We’ll know more by then.
Do you want to stay informed of all developments regarding smartwatches and other wearables?