HOW our bodies have changed over time. This week: Declining sense of smell
OUR sense of smell typically declines from the age of 70, as we lose nerve cells in the nose and produce less odour-holding mucus.
However, this increasingly appears to be happening earlier – because of air pollution.
One study, published in the journal Chemical Senses in 2006, compared the smell sensitivity of people living in Mexico City with that of a similar group from rural Mexico. The rural-dwellers detected smells of coffee and orange juice at lower concentrations than those from polluted Mexico City. This is thought to be because particles – such as those from car exhausts – can lodge in the lining of the nose and may also damage the olfactory nerve, which carries odour information from the nose to the brain.
Our sense of smell also affects our ability to taste, and a study last year, published in Obesity Reviews, found that the poorer a person’s sense of smell, the more likely they were to be obese.
In 2017 US expert Dr Kara Hoover had warned that pollution is affecting our sense of smell, and therefore taste, making us eat more.
© Solo dmg media
