Feeling lonely increased risk for all-cause dementia by 31 percent and cognitive impairment by 15 percent. Loneliness is a common — some would even say, universal — human experience.

Loneliness has been increasingly linked to heart attacks, strokes and other poor health outcomes, and now a new study shows it also raises the risk of dementia and cognitive impairment.

Loneliness isn't just associated with a higher risk of death, but also a higher risk of dementia, new research suggests. A meta-analysis of 21 studies involving more than 600,000 people finds loneliness is associated with an increased risk of cognitive impairment and dementia from any cause.