A decrease in the sense of smell is a harbinger of the imminent death of a person

The scent is lost – immediately in the coffin

Pavel Kotlyar, "Newspaper.Ru"

Elderly people who have stopped feeling odors do not have long to live – probably no more than five years. Scientists from the University of Chicago came to such frightening conclusions. Until 1987, canaries were used in British coal mines to indicate that the concentration of harmful gases in the chamber was exceeded. It turned out that the sense of smell for a person, or rather its absence, is a kind of canary, predicting that his departure is near.

In an article by Pinto et al. Olfactory Dysfunction Predicts 5-Year Mortality in Older Adults, published in the journal PLOS ONE, scientists have shown that a person's nose "knows" when he will die, and that the sense of smell can tell about the general health of an individual and his exposure to dangerous toxins.

Back in 2005-2006, Jayan Pinto from the University of Chicago conceived the idea of conducting a study among elderly residents of the United States on the subject of quality of life. It was attended by more than 3 thousand Americans aged 57 to 85 years. During the experiment, they passed a small test: they had to identify five smells (rose, leather, fish, orange and mint) in order to use the number of incorrect answers, scientists could determine the degree of loss of smell.

Five years later, the researchers decided to return to the experiment and try to find those who participated in the original experiment to repeat it. But not everyone could be found.

It turned out that 430 people (12.5%) are no longer alive, and these were not the oldest participants in the first experiment. Having raised its results, scientists were amazed to learn that 40% of those who died during their lifetime failed the smell test. And only 10% of those who died during their lifetime had a healthy sense of smell.

In other words, elderly people who have lost their sense of smell are four times more likely to die in the next five years than those who smell.

The scientists were even more convinced of their sad discovery by separating the result from other factors affecting the acuity of the sense of smell – nationality, gender, mental health and socio-economic status. The analysis showed that even an average loss of sense of smell can indicate that a person does not have long to live.

A: the proportion of people with aosmia, reduced and normal sense of smell
among those who died within 5 years in three age groups.
B: an increase in the probability of death depending on the number of errors in determining odors.
Graph from the article in PLOS ONE – VM.

"We think that the loss of the sense of smell is like a canary in a mine. It does not lead directly to death, but it is a harbinger, an early warning that something has gone completely wrong, that the violation has already happened. Our findings may lead to the creation of useful clinical tests, fast and inexpensive, identifying patients at risk," Pinto believes.

Medical statistics have shown that even such common diagnoses as cancer, heart failure or lung diseases cannot serve as such an accurate harbinger of death as loss of sense of smell.

And only severe liver damage can happen with the same indication. However, doctors emphasize that the loss of the ability to recognize odors is not the cause of death in itself, but serves as a harbinger. And biologists have two hypotheses to explain this phenomenon.

The olfactory cortex of the brain is one of the few places where new neurons are born from stem cells throughout life. The appearance of new cells responsible for the sense of smell slows down with age, and it looks like a loss of sense of smell. Therefore, the loss of sense of smell may indicate that the body loses the ability to reproduce cells and "repair" itself.

In addition, the olfactory nerve is also the only part of the nervous system in contact with air. As a consequence, this gives poisons and pathogenic bacteria direct access to the brain. Therefore, the loss of sense of smell can serve as an early warning of what may soon cause death.

Pinto and his colleagues did not find out what actually caused the death of 430 participants in the experiment, the answer to this question can give many interesting results. In addition, they are not sure that similar statements are suitable for younger people.

Age-related loss of the ability to recognize odors definitely affects the quality and lifestyle. "The smell affects the taste of food. Many people with a reduced sense of smell lose the pleasure of eating. They do not choose dishes well, they receive few useful substances. They can't tell when the food is spoiled, just like they can't sense a gas leak or the smell of smoke. They lose control of their own hygiene. Among all human senses, the sense of smell remains the most underestimated," Pinto concludes.

Portal "Eternal youth" http://vechnayamolodost.ru03.10.2014