Losing your sense of smell could be an early warning sign of Alzheimer’s disease, according to a new study.
The study, published in JAMA Neurology, found that older people who had worse senses of smell were more likely to have mental difficulties which progressed to Alzheimer’s disease.
The study’s findings suggest that sense of smell could be used to help screen for cognitive impairment, Alzheimer’s disease, and possibly other forms of dementia.
The study looked at 1,400 seniors with an average age of 79 and normal mental functioning. The researchers conducted intermittent smell tests on the participants, in which they had to scratch and sniff different odors and choose the correct answer from four options. The smells included both food and non-food odors, including banana, turpentine, onion, gasoline, and paint thinner.
After a follow-up period of 3.5 years, 250 people developed mild cognitive impairment. Mild cognitive impairment is an early stage of mental decline which can involve problems with memory and judgement. While it does not significantly affect day-to-day life, it can lead to dementia and declining mental health.