How Your Sense of Smell Could Protect Against Alzheimer's Disease

New research highlights a strong link between smell and brain health. Studies show that a declining sense of smell may signal risks for neurodegenerative diseases like Alzheimer’s. Meanwhile, activities that engage the olfactory system—such as cooking or smelling coffee—could help protect memory and even slow cognitive decline. A 2024 study identified connections between olfactory decline and 139 neurodegenerative conditions, including Alzheimer’s and dementia. The findings suggest that losing the sense of smell might serve as an early warning sign for these diseases.

The olfactory system connects directly to the hippocampus, the brain’s memory centre. A 2016 study found that master sommeliers, who constantly train their sense of smell, develop thicker memory regions in their brains. Researchers believe this increased thickness may offer some protection against conditions like Alzheimer’s. For those with impaired smell, therapies like smell retraining (SRT) can help restore function. However, a 2023 study revealed that 24% of COVID-19 patients with smell loss only partially recovered, while 3% saw no improvement at all. Some experts now suggest that practical activities, such as cooking classes, could be even more effective than traditional SRT in reviving the sense of smell. Everyday habits, like smelling perfume or freshly brewed coffee, might also play a role in keeping the olfactory system active. A survey by the Global Brain Health Institute found that over half of respondents fear memory loss, underscoring the importance of simple, preventive measures.

The research points to a clear connection between smell, memory, and long-term brain health. Engaging the olfactory system through training or daily activities could help maintain cognitive function. For those at risk, early interventions—like cooking or targeted smell exercises—might offer a practical way to support brain health over time.