Feeling lonely for long periods may do more than affect your mood. Experts say it can alter brain function and increase the risk of cognitive decline. Loneliness is often viewed as an emotional challenge, but its effect can extend far beyond mental well-being. Growing evidence suggests that chronic loneliness and social isolation can have a significant impact on brain health, potentially affecting memory, decision-making, cognitive function, and even long-term neurological outcomes. (Also read: Cricketer Axar Patel’s ‘worst diet’ included tea, puffs and no breakfast; says one protein habit transformed his routine )Social isolation impacts brain health, increasing the risk of cognitive decline. (pixabay)In an interview with HT Lifestyle, Dr Kunal Bahrani, Chairman and Group Director, Neurology at Yatharth Hospitals, explained that social connection plays a vital role in brain health, as regular interactions help stimulate cognition, regulate emotions, and maintain healthy stress responses.“When a person experiences prolonged loneliness, the brain can remain in a state of heightened alertness, leading to increased levels of stress hormones such as cortisol,” Dr Bahrani explains. “Over time, this may affect sleep quality, concentration, memory, and mood.”How loneliness changes the brainResearch has linked chronic loneliness to changes in areas of the brain responsible for emotions, learning, and decision-making. Reduced social interaction may also limit the mental stimulation needed to maintain cognitive flexibility and resilience as people age.“Social connection is to the brain what exercise is to the body,” says Dr Bahrani. “Conversations, shared experiences, and relationships continuously activate different cognitive networks. When those interactions decrease, the brain receives less stimulation.”Loneliness can also indirectly affect neurological health by influencing lifestyle habits. People who feel socially isolated may be more likely to experience poor sleep, reduced physical activity, unhealthy eating habits, or substance dependence, all factors associated with poorer brain health.Loneliness is the most harmful out of everything that falls under the umbrella of social disconnectedness. (Shuttersto)A risk factor for dementiaDr Sreenivas UM, Neurologist at Apollo Speciality Hospitals, Vanagaram, Chennai, notes that loneliness is becoming increasingly common in today’s digital world and is now being recognised as an independent risk factor for dementia.“Newer studies have shown that loneliness can produce structural changes in the brain, particularly in regions involved in memory, reasoning, thinking, and decision-making,” he says.The impact can be even more pronounced among people living with neurological conditions such as stroke, epilepsy, Parkinson’s disease, multiple sclerosis, or dementia. According to Dr Sreenivas, social isolation may worsen symptoms, delay recovery, and increase the risk of relapses despite ongoing treatment.Why ‘heartache’ feels realScientific studies have also found that loneliness activates some of the same brain regions associated with physical pain, providing a neurological explanation for why emotional distress can feel physically painful.“Functional imaging has shown that the areas affected by loneliness are similar to those activated during physical pain, giving scientific basis to the term ‘heartache’,” says Dr Sreenivas.Over time, prolonged loneliness may reduce activity in the brain’s reward pathways, making social interactions feel less satisfying. This can create a vicious cycle in which individuals withdraw further, leading to increasing isolation and declining brain health.Chronic loneliness substantially impacts brain health, comparable to obesity and smoking risks. (Shutterstock)Comparable to other major health risksThe consequences of chronic loneliness may extend beyond cognitive decline. Dr Sreenivas points to a large meta-analysis involving approximately three million people, which found that chronic loneliness increased the risk of premature death by 26%. “This makes loneliness almost as significant a health hazard as obesity and physical inactivity, and close to the risk associated with smoking,” he says.Can effects be reversed?The good news, experts say, is that loneliness is not a permanent state and the brain retains the ability to adapt and change.Meaningful social relationships, learning new skills, engaging in hobbies, exercising regularly, and participating in community activities can all help support cognitive health. Importantly, experts stress that quality matters more than quantity when it comes to social connections.“The goal is not to be surrounded by people all the time,” says Dr Bahrani. “Even a few strong and meaningful relationships can have a protective effect on the brain.”While loneliness is often discussed as an emotional issue, neurologists increasingly view it as a brain health concern as well. As research continues to uncover the links between social isolation and cognitive decline, experts say recognising and addressing loneliness early could play a key role in protecting both mental well-being and long-term neurological health.Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.Akanksha Agnihotri is a lifestyle journalist with over 3 years of experience. She is a psychology graduate and holds a postgraduate diploma in Radio and Television Journalism from the Indian Institute of Mass Communication, Delhi, where she graduated as a gold medalist. Originally from Bhopal, the beautiful capital of Madhya Pradesh, she draws inspiration from the city’s rich cultural heritage and layered storytelling traditions that subtly shape her narrative voice.