Ohio Scientists Create Wearable Device to Restore Smell

For 51-year-old pastor Jeremy Klein, losing his sense of smell to COVID meant a year without the aroma of fresh coffee or chocolate. Then he tried a prototype device at Ohio State University and everything changed.

"I could smell just about everything," Klein says. "I had not been able to smell chocolate or coffee for a whole year, and I could smell it with those things in my nose."

Unlike hearing loss or vision problems, smell loss has never had a real treatment option. No implants, no aids, nothing. Researcher Kai Zhao at Ohio State's otolaryngology department decided to change that.

Zhao's solution is surprisingly simple. He developed a nasal foam plug and a clip (similar to what synchronized swimmers use) that redirects airflow inside the nose to the olfactory region where smell happens. Think of it like a hearing aid, but for your nose.

The science is straightforward. Only a tiny fraction of the air we breathe actually reaches the olfactory cleft, the spot where our brain processes smell signals. Zhao's devices increase that airflow, amplifying the smell signal naturally.

The team published their first prototype results in March 2025 in BMC Medicine. Since then, they've been refining the design with 3D printing technology. In April 2026, they presented even better results.

The device doesn't work for everyone. Zhao explains that patients need some residual smell function, just like hearing aids only work if you have some hearing left. But for those with partial smell loss, the results have been remarkable.

Why This Inspires

Klein took his prototype home and now uses it while cooking for his family. His wife laughs when she catches him putting the device in his nose just to smell what's on the stove, but he doesn't care.

More than half of patients surveyed said they'd be willing to use the device regularly, as long as it works. Klein's only criticism? The current version is black and the plugs stick out, making it awkward to wear in public.

Thomas Hummel, who leads the Smell and Taste center at Dresden University of Technology, calls Zhao's work commendable. The research represents a genuine first step into treating a condition that affects millions but has been largely ignored by medicine.

The team is now working on making the device sleeker and more practical for daily life. They haven't collected long-term data yet, but the early results show real promise for people who thought they'd never smell their favorite things again.

As Klein puts it: "If they can figure out a way to design this that is sleek, they're onto something."