In Alan Sillitoe's 1962 classic British film, “The Loneliness of the Long Distance Runner,” a reform school student (Tom Courtenay) makes a name for himself with his ability to run great distances flat out.

Loneliness has been a recurring theme of British life (from Mary Shelley's “Frankenstein” to Jean Rhys' “Good Morning, Midnight”), but recently it's gotten so pervasive that the prime minister appointed a minister for loneliness to try to reverse the trend.

Here in the U.S., it's also epidemic. At any given time, around 43 percent of people say they're lonely. Young, heavy users of social media are at the greatest risk.

Former U.S. Surgeon General Vivek Murthy says loneliness can be worse for you than smoking 15 cigarettes a day. It heightens your risk of depression and anxiety and increases your risk for cardiovascular disease and dementia

It doesn't have to be that way. Using the UCLA Loneliness Scale, Cigna Health found that those who lived with others, got the right amount of sleep, work, and exercise, and interacted with family and friends scored the best.

So log off of social media (unless you're using a dating app) and cultivate some in-person relationships. Opt for face time, not Facebook time.

Call an old friend. Make plans to see family. Join a walking club or volunteer in your community. It could save your life.

A study published in the journal Psychophysiology found that close relationships — especially high-quality, romantic relationships — are consistently associated with positive physical health outcomes.