Smelling in the old age
Several authors argued that ageing is accompanied by an impairment of olfactory abilities, i.e., the ability to perceive an odour or a taste. However, beyond this overall effect of age on chemosensory abilities, ageing is accompanied by variability in olfactory performance: the decline of odour perception with age is not uniform across odorants neither across elderly individuals. Decline in odour perception may not be inevitable to the aging individual and that factors secondary to aging, such as poor health status or cognitive decline, may contribute to deficits in odour detectability beyond the age effect per se
« Sense of smell? I never gave it a thought. You don’t normally give it a thought. But when I lost it – it was like being struck blind. Life lost a good deal of its savour – one doesn’t realise how much “savour” is smell. You smell people, you smell books, you smell the city, you smell the spring – maybe not consciously, but as a rich unconscious background to everything else. My whole world was suddenly radically poorer… » (Oliver Sacks, The Man who Mistook his Wife for a Hat) (1)ù
In 1984, Richard Doty and his colleagues (2) asked 1,955 persons ranging in age from 5 to 99 years to complete a “scratch ‘n sniff” olfactory test. This test consisted of 40 different “scratch and sniff” strips which were embedded with a microencapsulated odorant. After each scent was released, the respondent smelled and identified the odour from four choices. Results revealed that peak performance occurs in the third through fifth decades of life (between 20 and 50 years) and declined markedly after the seventh (2). In line with this huge survey, several authors claimed that our olfactory sense decline as we grow old (3,4). Actually, elderly people belie ...