Memory Digest

Social Connection

Loneliness and social isolation are linked to higher dementia risk; learn what the research shows, the difference between being alone and feeling lonely, and simple ways to stay connected at any age.

Last reviewed: October 2026

Humans are social creatures, and our brains seem to depend on it. A growing body of research links loneliness and social isolation with a higher risk of memory loss and dementia, along with heart disease, depression and other problems.

The encouraging part: social connection is something almost anyone can build, at any age.

Loneliness vs. social isolation

The National Institute on Aging (NIA) explains that these are related but different:

• Social isolation is having few social contacts and few people to interact with regularly.
• Loneliness is the distressing feeling of being alone or separated.

You can live alone and not feel lonely, and you can feel lonely in a crowded room. Both matter for health.

What the research shows

Dementia risk. A 2015 review that combined 19 long-term studies found that people with less frequent social contact, low social participation, or more loneliness were roughly 40% to 60% more likely to develop dementia.

One of the 14 risk factors. The 2024 Lancet Commission on dementia, a major international review, lists social isolation in later life as one of 14 modifiable risk factors. It estimated that social isolation accounts for about 5% of dementia cases worldwide, one of the larger shares among the 14. See Reducing Dementia Risk: The 14 Risk Factors.

Wider health effects. The NIA notes that loneliness and isolation are associated with higher risks of high blood pressure, heart disease, weakened immunity, anxiety, depression, cognitive decline, dementia and earlier death.

Why might connection protect the brain?

Scientists are still working this out. Likely reasons include:

• Conversation is a workout. Following a discussion, remembering names and responding all exercise attention, memory and language.
• Cognitive reserve. A busy, engaged life may help the brain cope with damage for longer (see Cognitive Reserve).
• Less stress and depression, both of which affect the brain (see Stress, Anxiety and Memory).
• Healthier habits. The NIA notes that lonely people are more likely to be inactive, drink too much, smoke and sleep poorly.

It can also work the other way: early memory changes can make people pull back from social life. So withdrawal can be a warning sign as well as a risk.

Who is at higher risk?

The NIA points to life changes that often come with age:

• Hearing, vision or memory loss, which make conversation harder
• Disability or trouble getting around, including giving up driving
• Loss of a spouse, family or friends
• Retirement, moving, or living alone
• Caregiving, which can crowd out other relationships (see Caregiver Stress and Burnout)

Simple ways to stay connected

You don't need a big social circle. Regular, meaningful contact is what counts.

• Fix hearing and vision first. Hearing aids and up-to-date glasses make conversation easier and less tiring (see Hearing Loss and Dementia and Vision Loss and Dementia).
• Make a standing date. A weekly phone call, Sunday dinner, or coffee with a friend.
• Combine movement and company. Walking groups, exercise classes, dancing, golf or gardening clubs.
• Volunteer. Schools, libraries, food banks, hospitals and faith communities often need help, and volunteering gives a sense of purpose.
• Learn something new with others: a class at a community college, library or senior center (see Learning New Skills at Any Age).
• Use technology. Video calls with grandchildren, online groups, or a smartphone set up with large icons.
• Join a group built around a shared interest: a choir, book club, card game, or religious group.
• Check your local senior center or call the Eldercare Locator (1-800-677-1116) to find programs and transportation.
• Try a pet, if you can care for one; pets can bring routine, walks and conversation.

If someone you love has dementia

Social connection matters just as much after a diagnosis. Adult day programs, memory cafés, early-stage groups and simple visits all help. See Staying Active and Engaged, Living Well with Dementia and Finding a Support Group.

If you feel lonely

Loneliness is common and nothing to be ashamed of. Tell your doctor if you've been feeling lonely or down for weeks; depression is treatable (see Treating Depression for Brain Health). If you are in crisis or thinking about harming yourself, call or text 988 (the Suicide & Crisis Lifeline) any time.

Reaching out to one person this week is a good start.

Sources

1. National Institute on Aging: Loneliness and Social Isolation — Tips for Staying Connected
2. Kuiper JS et al. Social relationships and risk of dementia: A systematic review and meta-analysis of longitudinal cohort studies. Ageing Research Reviews, 2015
3. Livingston G et al. Dementia prevention, intervention, and care: 2024 report of the Lancet Standing Commission. Lancet, 2024

Not medical advice. This article is general information, not a diagnosis or treatment plan for any individual. Talk with a doctor about your situation.

Related articles

• Reducing Dementia Risk: The 14 Risk Factors
• Hearing Loss and Dementia
• Cognitive Reserve
• Exercise and the Brain
• Alcohol and the Brain