For all its warts, being online might be an overall positive for older people, new research suggests. The study found that reported regular internet use was associated with a reduced risk of dementia in those over 50. The largest possible benefit was seen in people who reported two hours or less of internet use compared to none.
The study was conducted by researchers from New York University. They analysed data from the Health and Retirement Study, a government-funded project that has tracked the wellbeing of a representative sample of older Americans via surveys conducted every two years. One of the many questions asked of people in the study is whether they use the internet.
The team focused on nearly 18,000 adults over 50 who were dementia-free at the start of the study and were followed for up to 17 years. They then divided the participants into two groups, based on whether they said they regularly used the internet in their initial survey. Another questionnaire assessed people’s cognition, which the researchers used as a measure for dementia status.
The authors found that regular internet users were half as likely to meet the criteria for dementia than those who reported no use at baseline, even after accounting for other factors like their pre-existing health. People who continued to report using the internet in subsequent surveys also appeared to have an even lower risk.
“Taken together, these findings suggest that regularly using the internet may be associated with cognitive longevity,” the authors wrote in their paper, published Wednesday in the Journal of the American Geriatrics Society.
This isn’t the first study to find a correlation between internet use and reduced dementia risk in older people. But the authors say their analysis is the longest of its kind to examine this possible relationship. The Health and Retirement Study is also a prospective study, meaning it proactively tracks people’s outcomes over time. These studies are generally better at rooting out a cause-and-effect link between two factors — in this case, internet use reducing dementia risk — than many other types of research.
There are still many questions remaining about this link, though. The authors also looked at data from a smaller sample of participants who reported how often they used the internet on a weekly basis. They found a possible U-shaped association between hours online and dementia risk, where people who spent the least and the most time online (between 6 to 8 hours a day) seemed to have the highest dementia risk. Meanwhile, the lowest risk was seen in those who spent two or fewer hours on the internet a day. However, the difference in risk for very online people wasn’t statistically significant, perhaps due to the smaller sample size available.
It’s likely that there is a point of diminishing returns, the authors say, where “excessive online engagement may have adverse cognitive effects on older adults.” But more research will be needed to find where this point is. And even if using the internet can help reduce dementia risk, this relationship could cut both ways, the authors note. People who develop dementia might start to use the internet less and less over time, for instance.
At the very least, this study should inspire other researchers to figure out the best balance between staying online and staying mentally sharp, the scientists say.
“Since a person’s online engagement may include a wide range of activities, future research may identify different patterns of internet usage associated with the cognitively healthy lifespan while being mindful of the potential side effects of excessive usage,” they wrote.