Losing your sense of smell not only spoils the enjoyment of food and fragrances, and reduces retrieval of smell-associated memories, it can also be hazardous to your health. What’s more, it’s not a rare problem. It affects about a quarter of people over 50.
It puts your health at risk in some ways that are obvious. Those who have lost most or all of their ability to smell are almost twice as likely to be unaware of a gas leak or fire, eat spoiled food or consume toxic substances.
One person even downed a full glass of jewelry cleaner, thinking it was water!
But that sort of health hazard is not what I’m thinking of today. Recent studies suggest that loss of smell is apparently linked to an increased risk of death in ways you’d never expect. . .
These are the disturbing findings. . .
Predicts Death More Accurately Than Cancer
Researchers from the University of Chicago enrolled 3,003 people aged between 57 and 85. They were tested for their ability to smell the odors of fish, orange, peppermint, leather and roses.
Of the 430 people who died during the following five years, almost four in ten had performed poorly on the test compared to two deaths for every ten people who performed moderately and a mere one in ten among those who had a keen sense of smell.
This means that those who had an impaired sense of smell – a condition called hyposmia – were almost four times as likely to die within five years compared to those who correctly identified all five smells.
The researchers took many factors into account that could affect the results, such as age, physical activity, illness, socioeconomic status and more. Even so, loss of smell predicted death more accurately than did a diagnosis of cancer, heart failure or lung disease.
It’s hard to believe, but a loss of the sense of smell means you’re more likely to die within five years than a person who’s received a cancer diagnosis.
In a new study published in March, researchers from Sweden tested the olfactory (smell) function of 1,774 people aged 40 – 90 and followed them up ten years later.
During the decade almost a quarter had passed away. Even taking account differences in age, sex, education and health, including dementia, the risk of death was associated with their ability to detect odors.
Of the 13 fragrances they were asked to identify, each incorrect answer increased the risk of dying. Those with complete olfactory loss (anosmia) had a risk of death almost 20% higher than those with normal function.
Lead author Dr. Jonas Olofsson said, “Our results were not explained by dementia…Instead mortality risk was uniquely predicted by smell loss. The sense of smell seems to be a good indicator of aging brain health. We see smell function as the canary in the coal mine.”
Tips To Hang on To Your Sense of Smell
Since portions of the olfactory system continually regenerate, it should be possible to keep the sense of smell for your whole lifetime.
The reasons for a gradual loss are not known, but could be because the olfactory nerve is exposed to the open air. Poisons and pathogens have a direct route to the brain and could cause damage over time.
Or perhaps the stem cells that regenerate the olfactory nerve cease to function. This could indicate that the body no longer has the ability to self-repair.
Whatever the reasons, there are some things we can do to maintain this ability.
- Engage in some form of exercise. One large study found those who worked up a sweat even once a week lowered their risk of olfactory impairment.
- Make sure you are not zinc deficient. It produces an enzyme that’s critical for smell. Good sources are chicken, lamb, grass-fed beef, pumpkin seeds, cashews, chickpeas, mushrooms and spinach.
- Frequently engage with fragrances. The idea that you can train yourself to improve smell function seems odd, but it is really no different than any other form of training.
If you are concerned about this issue you might want to get checked out by a specialist who may recommend a formal course of olfactory training (OT).
In typical OT studies, participants are told to sniff essential oils of rose, eucalyptus, clove and lemon for ten seconds each, twice a day for 3 months.
A review of ten such studies found that olfactory training was “a promising modality for the treatment of olfactory dysfunction.”