You don't consider yourself a lonely person generally, but sometimes have days where feelings of loneliness set in.

If you're one of those people, even that transient loss of connection with others could be impacting your physical health, a new study finds.

“A lot of research is focused on loneliness being a binary trait -- either you’re lonely or you’re not. But based on our own anecdotal lives, we know that’s not the case. Some days are worse than others -- even some hours,” explained study lead author Dakota Witzel.

“If we can understand variations in daily loneliness, we can begin to understand how it affects our daily and long-term health," said Witzel, a postdoctoral research fellow in the Center for Healthy Aging at Penn State University.

As Witzel's group noted, long term loneliness is a known health risk factor -- so much so that in 2023 U.S. Surgeon General Vivek Murthy labeled loneliness a public health crisis. He noted raised rates of depression and other mental health troubles tied to loneliness, as well as a 29% higher risk of heart disease, a 32% increased risk of stroke and a 50% increased risk of developing dementia in older adults.

But what about more temporary moments or days of loneliness?

In the study, Witzel's group looked at data on middle-aged Americans from the 1,538 participants in the National Study of Daily Experiences (NSDE). That effort is led by senior STUDY author David Almeida, a professor of human development and family studies at Penn State.

The NSDE conducted phone interviews with participants, tracking their emotional ups and downs each day over an eight-day period. The team also tracked any physical health issues participants might be having.

The result: The less lonely a person felt on a given day, the less likely they were to have everyday physical symptoms like fatigue or headache, Witzel's group found.

If such symptoms did appear, they were less severe on a "low loneliness" day than on a day the person was feeling more lonely.

The study was published recently in the journal Health Psychology.

“These findings suggest that day-to-day dynamics of loneliness may be crucial in understanding and addressing the health effects of loneliness,” Almeida said in a Penn State news release. “Increasing feelings of social connection even for one day could result in fewer health symptoms on that day. Such a daily focus offers a manageable and hopeful micro-intervention for individuals living with loneliness.”