Not everyone minds spending time by themselves — but people who feel lonely may be more at risk for health problems than those who don't.
"There's a big correlation between health and loneliness," says Norman Abeles, a professor emeritus of psychology at Michigan State University in East Lansing, Michigan. "If your health is poor, you're more likely to say that you're lonely."
Loneliness isn't exactly the same as isolation, although the two can be related, explains Abeles. "Loneliness is subjective, and relates to feelings of being alone," he says. "Social isolation [is being separated from] friends, family members, and other types of social support, and is presumably more objective."
The problem: As we age, we also tend to lose with others, either because we're battling a chronic illness or are no longer as mobile as we once were. And that lack of social interaction can take a toll on our health. Here's how:
1. It could boost your blood pressure.
People who are lonely often have higher systolic blood pressure levels than people who aren't lonely, according to the National Institute of Aging.
2. It's linked to depression.
"Loneliness is often related to feelings of depression, sadness, and avoidance of others," says Abeles. If it seems like a struggle to go about your daily routine — getting up in the morning, making your bed, cleaning the house — that's a sign that your loneliness may be sliding into depression and that you may need more help, he says.
3. It could interfere with your shut-eye.
"Sleeplessness is very commonly related to loneliness," says Abeles, in part because lonely people may be more prone to worrying, which can keep them awake at night.
"It's normal to do some worrying, but if you're worrying all the time — and about little things, as opposed to big things — that's a sign that…you may need to get some counseling if necessary," says Abeles.
4. It could raise inflammation levels in the body.
People who are more social tend to have lower levels of interleukin-6, a type of protein which has been linked to inflammation age-associated diseases like Alzheimer's, rheumatoid arthritis, and some cancers, according to the National Institute of Aging.
5. It could make you more sedentary.
Being physically active can boost your mood — but if you're lonely, you may not feel like exercising, says Abeles. Plus, he says, people who are lonely or are depressed may lose their appetite and not eat as much as they once did.
Still, Abeles cautions that loneliness isn't just a problem in seniors. "We tend to stereotype people," he says. "People just assume that older adults are [always] going to say they're lonely, but that isn't so."
Plus, as you get older, you also begin to pass through some of the major milestones: "[By the age of 70,] you've probably passed illness like cancer or stroke, or alcoholism or addiction," says Abeles. "All these things are more or less behind you."
If you are feeling lonely, however, or are experiencing signs of depression, talk to your doctor about whether you should seek additional help.