The Big 3 Risk Factors for Dementia

A British study identified the three most powerful risk factors for developing dementia: diabetes, air pollution and alcohol. These factors appear to affect certain brain regions that are particularly vulnerable to Alzheimer’s disease and schizophrenia. The new research was published in Nature Communications.

According to The Washington Post, these areas are “the first ones to go when we start aging,” said Gwenaëlle Douaud, an associate professor at the University of Oxford and co-author of the study. The research was based on brain scans of nearly 40,000 adults between the ages of 44 and 82 in Britain.

“What we’re trying to do is say: What are the common risk factors for dementia that are affecting these regions?” Douaud said. “These are the three most harmful but then, obviously, the others, they have an effect.”

The study identified 161 modifiable risk factors before boiling it down to the big three: a diagnosis of diabetes, the amount of nitrogen dioxide in the air, and how often someone drinks alcohol — from never to daily, or nearly every day. These were found to be the most detrimental risk factors to these vulnerable regions in the brain. While diabetes, air pollution and alcohol consumption had twice the negative effect as the other leading risk factors, the next major risk factors, according to the study, were sleep, weight, smoking and blood pressure.

The World Health Organization says that more than 55 million people are living with dementia globally and that figure is expected to almost triple by 2050. Dementia is defined as the loss of cognitive function, and the symptoms result from brain neurons losing their connection to other brain cells and eventually dying, says the Post.

Dr. Gill Livingston, lead author of a study published in Lancet in 2020 on dementia prevention and intervention, said that in her study about 40% of dementia cases had a dozen modifiable risk factors such as hypertension, hearing impairment, smoking and obesity. She said that the new study was “very interesting” although the study participants taken from the U.K. Biobank tend to be a healthier and more highly motivated group of people than the average cohort.

Still, she said, the study shows there is a lot people can do to reduce their risk of dementia. Douaud added that eating a variety of healthy foods to lower your blood sugar, taking measures to protect against “traffic-related pollution” and drinking alcohol in moderation are three steps that can reduce your chances of developing the disease.