Research shows that chronic loneliness can increase the risk of developing memory loss conditions like Alzheimer’s disease or other dementias, says Dr. Christina Chen, a geriatrician and internist at the Mayo Clinic, explaining that there are biological and behavioral mechanisms behind this.
Loneliness can trigger a chronic stress response that increases stress hormones and impairs the growth of neurons and their connections that are critical for learning and memory. Over time, this can accelerate brain aging.”
Chen says loneliness also leads to reduced cognitive stimulation, less social engagement, fewer novel conversations and reduces exposure to mentally stimulating environments. Without these “mental workouts,” brain networks that challenge memory, language and problem solving are impacted.
“From a behavioral and lifestyle perspective, lonely individuals tend to be less physically active, experience sleep disturbances, have poorer lifestyle choices and may delay medical care. They may also have a higher risk of mental health conditions such as depression, which itself is an independent risk factor for dementia.”
The Stats
In 2024, a meta-analysis of 600,000 individuals from multiple NIA-funded population-based studies found that those feeling lonely were associated with a 31 percent increased risk of developing dementia, including Alzheimer’s disease and a 15% increase in cognitive impairment (non-dementia memory/thinking decline).
“While loneliness, depression and social isolation can overlap and cause things to worsen, loneliness by itself is a biologically and psychologically distinct state. It remains a stand-alone predictor due to the underlying impact on the stress pathway, cognitive load and neurobiology,” Chen says. “This is why interventions that specifically address the feeling of loneliness (not just increasing social contact) are important for brain health.”
Social Isolation vs. Loneliness
“I have seen this in many patients and even in my own mother. After the COVID pandemic, many individuals who were socially isolated even for what seems to be a short period of time (months) have noticed cognitive changes. Social isolation measures how much contact you have with others. Loneliness measures how connected and emotionally
satisfied you feel in your relationships. You can spend most of your day alone, but may still feel fulfilled and not lonely. If you have meaningful relationships, feel content in your friendships, and understood by others, you can still have the autonomy you enjoy.
On the flip side, you can be surrounded by people and still feel lonely if you lack emotional closeness, feel misunderstood or don’t feel comfortable sharing your authentic self. The brain responds to loneliness, not headcount. It’s the quality of your relationships, not the quantity, that helps keep a deep, emotionally satisfying and reciprocal connection.”
Assessing Loneliness
Concern for a friend
Simply asking, “Are you lonely?” doesn’t often yield accurate insights because this can be subtle and hard to describe.
Chen says to look for symptoms of withdrawal from activities the person once enjoyed, decline in self-care, mood changes, irritability or restlessness. Focus more on functional and feeling-based questions, such as “Do you feel you have enough people to talk to?” “Do you feel there are people who understand you well?” “When was the last time you spent doing something you enjoy?”
Concern for yourself
The key to addressing your own loneliness is taking the time to discover what will work best for you. It often takes a bit of creativity to discover the right solutions. Some ideas:
- Optimize your connection circle. Identify three to five friends who truly empower you and lift you up, whether these are friends, neighbors or co-workers who you can intentionally connect with a few times a week. Make a concerted effort to make this part of your weekly routine.
- Keep your sense of purpose at the heart of your caregiving. Remind yourself why your role matters. Pair caregiving with social moments. For example, invite a friend or another caregiver to join you in an activity you do with the person you care for.
“I am currently caring for my cognitively impaired mother who has a bone marrow disorder and needs chemotherapy,” Chen says. “I take her for treatments a few times a week, and I go with my husband. We spend time with her, have coffee with her, and reminisce about memories that she recalls from my childhood. It turns a stressful moment into a joyful one.” - Strengthen your own daily joy rituals. Integrate small routines that elicit joy or happiness – morning coffee on the porch, play favorite music, meditate, walk your dog. These create predictable moments of comfort and satisfaction that build emotional resilience.
- Care for your body. This is important, Chen says. Don’t neglect yourself. Physical activity boosts mood and keeps you physically and functionally capable. Seek help without guilt. Make time for yourself to replenish your energy and maintain an uplifting mindset shift.
Loneliness doesn’t have to be a permanent state. It’s like a signal (such as hunger or thirst) telling us to seek connection. Use this signal as a prompt to make some changes in your life that can help you thrive.
Dr. Christina Chen is a geriatrician and internist at the Mayo Clinic in Rochester, MN, who cares for patients in the community and long-term care. Her passion and area of research are improving the quality of life for patients with dementia by transforming the living environment into a space of hope and joy.