How loneliness shrinks your brain: ‘Underappreciated public health crisis’

How loneliness shrinks your brain: ‘Underappreciated public health crisis’

Loneliness has emerged as a devastating health threat facing our society.

The US Surgeon General, Dr. Vivek Murthy, declared in May last year that the "epidemic of loneliness and isolation plaguing our nation has been an underappreciated public health crisis for far too long."

New research also finds a definitive link between the number and regularity of social contacts in healthy older adults and brain volume. Those with the fewest friends and interactions had smaller brains than other participants. In contrast, individuals who actively maintained the most connections through relationships had noticeably larger temporal lobes, occipital lobes, cingulums, hippocampi, and amygdalas, according to a thought-provoking study published last month in Neurology. Nurturing social ties plays a crucial role in brain health and staving off cognitive decline in our later years.

“Social isolation has been associated with … premature mortality, increased risk of coronary heart disease and stroke, increased reporting of depressive symptoms, as well as increased dementia risk,” Dr. Alexa Walter and Dr. Danielle Sandsmark of the University of Pennsylvania wrote in an accompanying editorial.

To understand the impact of social contact on brain health, researchers from Kyushu University in Japan studied thousands of elderly men and women, analysing their MRI brain scans and inquiries regarding social interaction frequency. The investigation observed over eight thousand seniors, questioning how often companionship was garnered from friends or relatives residing elsewhere—daily, several times weekly, several times monthly, or seldom.

Previous studies have indicated that social seclusion correlates with numerous unfavourable wellness consequences. Those reporting the fewest social exchanges demonstrated brain volumes noticeably smaller than those with more social exchanges. Furthermore, those experiencing isolation revealed more lesions of white matter—brain regions impaired—than people maintaining consistent contact. The findings reiterate human bonds' indispensable role in preserving cognitive functions as individuals age.

“While this study is a snapshot in time and does not determine that social isolation causes brain atrophy, some studies have shown that exposing older people to socially stimulating groups stopped or even reversed declines in brain volume and improved thinking and memory skills,” study author Toshiharu Ninomiya told Neuroscience News.

Elderly individuals with abundant social interactions frequently maintain more lucid cognitive functions. Maintaining engaged social lives may support healthier brain aging.

This insight supplements a growing body of data corroborating that loneliness constitutes a serious public health crisis worldwide. Experiencing isolation and a lack of community can negatively impact well-being in many ways.

Interestingly, loneliness afflicts more than just the aged or infirm. Gen Z, coming of age in an era of digital connectivity, also reports high levels of feeling detached and separated. Nearly four out of five teenagers and young adults articulated experiencing isolation, double the percentage of senior citizens. Societal shifts may be exacerbating loneliness across many demographics.

“Given the significant health consequences of loneliness and isolation, we must prioritise building social connection the same way we have prioritised other critical public health issues such as tobacco, obesity and substance use disorders,” Murthy stated.

“Together, we can build a country that’s healthier, more resilient, less lonely and more connected.”