Updated 04 August 2015

If you can't smell these 5 things you might be dying

Researchers have found that having a poor sense of smell is strongly associated with dying within the next 5 years.


Smell is usually considered one of the less essential senses compared to abilities like vision and hearing. However, a new study suggests that your sense of smell, or lack thereof, could be giving you clues about potentially catastrophic health issues.

The study used five aromas: peppermint, orange, fish, rose and leather. An inability to distinguish these scents was a strong indicator of death within 5 years. Those who failed to smell the scents were almost 6 times more likely to be dead within that timeframe, reported the Economist.

While the study, which was conducted by the University of Chicago and published in PLOS ONE, might seem to have a strange premise, there is strong scientific reasoning behind it. A poor sense of smell has been linked to a number of common medical ailments such as cancer, Alzheimer’s and Parkinson’s.  It s also associated with premature shortening of the telomeres which leads to accelerated ageing.

Read: Poor smell linked to poor memory

The study took 3005 participants aged between 57 and 85 and administered a simple smelling test. Depending on how many of the smells they could identify, participants were placed into one of three categories: normal, smell-deficient, or unable to smell.

A follow up study was conducted after 5 years, in which time 430 of the respondents had died. The deaths were then attributed to the appropriate categories from which the following breakdown was derived.

Normal smelling: 10% dead
Smell-deficient: 19% dead
Unable to smell: 39% dead

These findings were then adjusted to account for age, socioeconomic status, gender and age after which the correlation was still found to be statistically significant.

Read: Lifetime of learning might thwart dementia

The suggestion is not that the loss of smell is the causes of death, but rather that it is a sign of underlying health issues that are about to cause serious problems. It is posited that because smell requires a frequent turnover of stem cells, diminishing capabilities here are a result of the body’s overall inability to regenerate itself. This has a clear link to neurodegenerative disorders like Alzheimer’s, as well as cancer which is a result of the improper growth of new cells.

The researchers concluded that scent tests could form a valuable medical tool, especially in the field of geriatric care, say PBS.

Read more:
Artificial noses on the way
Alzheimer's why early detection is important 
How we smell



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