28-05-2025
Smart Dental Floss Tracks Levels Of Stress Hormone Cortisol In Saliva
Scientists have created a dental floss that doesn't just clean between your teeth. It gauges your stress levels.
It does that by measuring amounts of cortisol in saliva. Produced by the adrenal glands and often referred to as 'the stress hormone,' cortisol plays a critical role in regulating the body's response to stress, in addition to regulating blood pressure, helping control the sleep-wake cycle and influencing other physical functions.
Chronic stress can impact us in all sorts of adverse ways — from increasing the risk of cardiovascular disease to decreasing immune function — so controlling and reducing it is essential. The Tufts University team behind the multitasking floss aimed to create a low-cost, noninvasive and simple at-home tool for getting a read on stress levels in real time.
'We didn't want measurement to create an additional source of stress,' Tufts engineering professor Sameer Sonkusale said in a statement, 'so we thought, can we make a sensing device that becomes part of your day-to-day routine?' Sonkusale and his colleagues detail their saliva-sensing dental floss in the journal ACS Applied Materials & Interfaces, and are creating a startup to try and bring the product to market.
The dental floss comes in the form of a standard floss pick, with the string stretched across two prongs that extend from a plastic handle. It's not just any string, though. It's a special 3D-printed thread containing a narrow channel that picks up the saliva via capillary microfluidics, or blood vessel activity that moves the fluid along. The spit then gets drawn into the flat pick handle and into an attached tab, where it spreads across cortisol-detecting electrodes and produces a score within 11 to 12 minutes.
'Combined with a wireless readout, this saliva floss offers a convenient way to monitor daily stress levels," the study says.
The team tested the device on student volunteers at the Boston university, resulting, according to the study, in highly accurate results reinforced by those of ELISA kits that test a range of antigen targets, hormones and molecules. Still, Sonkusale said the smart floss is best used for monitoring rather than diagnostics, where blood work remains the gold standard.
'But once you are diagnosed and put on medication, if you need to track, say, a cardiovascular condition over time to see if your heart health is improving, then monitoring with the sensor can be easy and allows for timely interventions when needed,' he said.
The novel device, the scientists say, could be extended beyond cortisol to detect other salivary biomarkers, such as estrogen for fertility tracking, glucose for diabetes monitoring and even markers for cancer — turning a simple daily dental act into a broader health check-in.
