Last month, the big news from the annual Alzheimer's Association International Conference (AAIC) 2019 in Los Angeles was that various lifestyle factors may offset risk.

All told, five research studies were presented that focused on specific lifestyle interventions (e. ., regular exercise, healthy , cessation, limited consumption, and cognitive stimulation) that appear to counteract the genetic (and overall) risk for and dementia. The latest research presented at AAIC 2019 suggests that boosting cognitive reserves through lifestyle choices promotes a wide range of neuroprotective benefits associated with a lower risk of dementia. (See "Avoiding Alzheimer's" and "Four Lifestyle Choices May Offset Risk of Cognitive Decline.")

Source: Pixabay

To the best of my knowledge, social contact was not on the list of lifestyle factors associated with a lower risk of dementia presented last month at AAIC. That said, this month, a new longitudinal study (Sommerlad et al., 2019) led by researchers at University College London (UCL) reports that frequent social contact around age 60 is associated with a lower risk of dementia later in life.

This paper, "Association of Social Contact with Dementia and Cognition: 28-year Follow-up of the Whitehall II Cohort Study," was published on August 2 in PLoS Medicine. "Our analysis suggests that more frequent social contact during early and may build cognitive reserve, which is maintained and delays or prevents the clinical expression of dementia," the authors said.

For this study, the researchers analyzed data collected on six occasions between 1985 and 2013 from over 10,000 respondents (with an average age of 45 when the study began), who were asked about the frequency of their social contact with friends and family. The UCL-led research team focused on the amount of social contact each participant had at ages 50, 60, and 70, along with subsequent reports of dementia. The main goal of their analysis was to investigate a potential link between social contact and .

Data analysis revealed that higher amounts of social contact at age 60 were most significantly associated with a lower risk of developing dementia later in life. Those who had daily face-to-face interactions with friends at age 60 were 12 percent less likely to develop dementia than age-matched cohorts who weren't socially engaged on a regular basis.

Although the link between social contact and dementia risk was less statistically significant at ages above and below 60, the researchers speculate that, in the long run, staying socially active across a lifespan may help to protect against dementia.

"Here, we've found that social contact, in middle age and late-life, appears to lower the risk of dementia. This finding could feed into strategies to reduce everyone's risk of developing dementia, adding yet another reason to promote connected communities and find ways to reduce isolation and ," the study's lead author, Andrew Sommerlad from UCL , said in a news release.

Why would increased social contact decrease someone's risk of dementia?

"People who are socially engaged are exercising cognitive skills such as and language, which may help them to develop cognitive reserve—while it may not stop their brains from changing, cognitive reserve could help people cope better with the effects of age and delay any symptoms of dementia," senior author Gill Livingston of UCL Psychiatry said in statement. "Spending more time with friends could also be good for mental well-being, and may correlate with being physically active, both of which can also reduce the risk of developing dementia."

Although this 28-year follow-up study provides some of the most robust evidence to date of a possible link between social contact and dementia risk, these findings are correlative; the research does not conclude that social contact causes lower risks of dementia.

Notably, this research on the correlation between social contact and dementia risk has some significant limitations.

The first chicken-or-the-egg question healthy skeptics might ask: Do people who are less likely to develop dementia seek social contact because they already have robust cognitive reserves, or does social contact itself help to maintain cognitive reserves and stave off dementia? The authors address this limitation of their analysis: "An alternative explanation for our findings is that early cognitive differences could affect individuals’ subsequent ability to establish and maintain social relationships, as well as increase susceptibility to later dementia."

This study has another noteworthy limitation: The researchers relied on health records to ascertain if someone had experienced dementia later in life. As the authors explain, "A limitation is that our study derived cases of dementia from health records, which has the potential to miss cases of dementia in people who are more socially isolated, which would be likely to underestimate the association between social contact and dementia."

Nevertheless, taken together, there is a growing body of evidence that lifestyle choices may offset dementia risk. Many of the recommendations for staving off dementia echo the exact same advice that has been associated with a healthy lifestyle for eons: Don't smoke, stay physically active, eat a nutritious diet, limit alcohol consumption, and keep your brain stimulated. Now, it seems we can add social activity to this list.

Blogger's note: Although the above-mentioned prescriptive advice for delaying cognitive decline may not seem earth-shattering to many readers, in my opinion, it's helpful to have a checklist of specific daily habits that have neuroprotective benefits.

In terms of optimizing your cognitive reserves, is there one (or more) lifestyle factors on this list that you'd like to address? Ask yourself: "Do I overeat junk food, smoke , binge on alcohol, skip regular workouts, veg out too much, or avoid social engagements?" Which of these behaviors would you like to change?

My answer to this question: "I need to make more of an effort to have regular face-to-face social contact with friends." I'm a loner by nature, but these days, as a 53-year-old, I spend much more reclusive time reading and writing by myself than when I was younger. In recent years, I've become increasingly prone to seeking self-determined solitude. I love being alone.

That said, whenever I force myself to meet a friend for a coffee klatsch or agree to attend an often-dreaded social event, I leave feeling invigorated and intellectually stimulated. Anecdotally, it seems that the free-flowing conversation skills required to socialize effectively flex parts of my brain that would lay dormant and atrophy without social contact.

Although I don't believe all of us can (or should) force ourselves to become social butterflies in an attempt to offset cognitive decline, the latest research suggests that staying socially active—to the degree that fits your —can boost cognitive reserves and may reduce dementia risk.