Researchers: If you can't smell, you may have higher risk of developing dementia

How good is your sense of smell?

University of Chicago researchers say there are five specific smells that if you can't detect, could help doctors determine your risk of developing dementia. 

Mary Spainhour is taking part in a smell test at the University of Chicago. Her job is to sniff pen like devices and identify certain odors.

This test was part of a study given to older people across the country. It found those who couldn’t identify 4 out of 5 common odors were twice at risk of developing dementia. And the worse their sense of smell, the bigger the risk.

Dr. Jayant Pinto is the study's lead author. He says the findings add to growing evidence that the first damage to the brain occurs in olfactory neurons, which distinguish between different aromas

"The olfactory nerve which sits in top of your nose is plugged in directly into your brain and so it is connected to your brain and it manifests and it's a reflection of a window into your brain,” Dr. Pinto said.

Dr. Pinto says losing one's sense of smell is a strong indicator of significant damage and that this simple test could provide a quick and inexpensive way to identify those who are already at high risk 5 years before symptoms develop. That's important because right now, dementia can go unnoticed for up to 20 years with no accurate way to spot the irreversible damage. 

"If we can know who's at risk then we can put those people in clinical trials for new drugs that might prevent them from getting Alzheimer’s,” Dr. Pinto said.

And he says a larger study has determined it's not just smell that makes a difference. They also found that a natural decline of the five classical senses: vision, hearing taste and touch can predict a number of poor health outcomes, including our risk of death. People who had sensory impairment issues moved slower and had greater difficulty performing daily activities.

So what's the take home message?

"Make sure older people have glasses, hearing aids if they need older people can use those senses in their daily lives to keep them healthy and keep them alive,” Dr. Pinto said.

The key may be something we already know, but worth repeating: exercise, eat right and take care of yourself to have the healthiest life possible as we age.