The bills we have to pay keep us up at night more often than we’d like. But could we be losing more than sleep – could we be losing our minds too?

A new study that followed people for decades answers in the affirmative, finding that low income and the inability to cover basic financial obligations are linked to worse cognitive performance in middle age and greater brain atrophy later in life.

The findings are presented by Jacques Wels, lead researcher at University College London’s (UCL) Centre for Longitudinal Studies in Health and Ageing, in an article for The Conversation discussing the study, which was published in Innovation in Ageing.

How the study was conducted

Researchers drew on data from the British 1946 birth cohort study, one of the longest-running population studies in the world. The study’s origins lie in the economic anxieties of the 1930s, when the Great Depression left many families struggling with their finances and the cost of raising children, making it an ideal dataset for revisiting the same questions decades later, the researcher notes.

The analysis included 2,759 people, whose household income was recorded at ages 26, 43 and 53. Persistently low income was defined as falling into the bottom 20% of the sample at at least two of these ages. Participants were also asked whether they struggled to make ends meet or pay their bills at various points between the ages of 36 and 53. Roughly one in six had persistently low income, while one in eight experienced recurring financial hardship.

What researchers discovered

At age 53, participants underwent tests of verbal memory and information processing speed. Those who had experienced more financial strain performed worse, even after the researchers accounted for education level, childhood cognitive ability and the socioeconomic conditions in which they grew up.

A smaller subgroup of participants also underwent brain imaging scans between the ages of 69 and 71, with similar results. Persistently low income was linked to greater brain shrinkage, a marker associated with poorer brain health. The association appeared stronger in men, in those who grew up in disadvantaged circumstances, and in individuals with a higher genetic predisposition to Alzheimer’s disease.

For men of this generation – born in 1946, when the model of the man as the family’s main breadwinner still prevailed – the pressure to secure household income likely made financial stress even more acute, the researcher explains. However, the researchers note that these particular findings were based on smaller subgroups and require further confirmation.

How does financial stress affect the brain?

One possible explanation for this effect on brain function is chronic stress, according to the researcher. Long-term activation of stress mechanisms can increase inflammation and accelerate processes linked to brain ageing. A simpler explanation is that the constant worry over money consumes mental energy.

The endless calculations involving bills, debts and everyday needs create a persistent cognitive load, leaving fewer mental resources available for memory, concentration and decision-making.

“We recognise that our study cannot prove a cause-and-effect relationship, and that the results, which come from a single generation of British adults, may not apply directly to other populations or countries. Still, following the same people over such a long period gives us a far more reliable picture than studies that look at only a single point in time.

Financial hardship is now recognised as one of the factors that, alongside hearing loss, smoking and physical inactivity, can influence the risk of cognitive decline in later life. Our findings suggest that reducing chronic financial pressure among working-age adults, regardless of the country they live in, could help protect brain health and potentially reduce future rates of dementia,” the researcher concludes.