50 years ago, scientists suspected that lost sense of smell could be restored

P.P.C. Graziadei and J.F. Metcalf of Florida State University have been producing … ever more detailed, evidence for olfactory nerve regeneration in mammals…. Might olfactory nerves be regenerated in people who have trouble smelling, thereby restoring or improving their sense of smell? “The phenomena of regeneration are applicable to all vertebrates and most likely to humans,” says Graziadei.

Update

The scientists’ hunch was right on the nose: The human cells that detect scent information and send it to the brain can replenish themselves, though exactly how is unclear. Experimental therapies to help people who have lost their sense of smell due to COVID-19 could help researchers figure it out (SN: 9/24/22, p. 14). Smell training, which involves regularly and deeply smelling various scents, might rewire cells’ connections to the brain or stimulate new cell growth. Treating damaged cells with steroids and blood plasma might aid healing. More invasive treatments such as nasal lining transplants aim to boost regenerative stem cells.