Suffering from a cold is annoying enough, but if you are lonely, the chances are you would feel even worse, a study says.

People who feel lonely are more prone to report that their cold symptoms are more severe than those who have stronger social bonds, said the study published in the journal Health Psychology.

"loneliness puts people at risk for premature mortality and all kinds of other physical illnesses," said one of the researchers Angie leRoy from Rice University in Houston, Texas.

"But nothing had been done to look at an acute but temporary illness that we're all vulnerable to, like the common cold," leRoy added.

The researchers drew a distinction between feeling lonely and actual social isolation.

"You can be in a crowded room and feel lonely. That perception is what seems to be important when it comes to these cold symptoms," leRoy said. 

Carrying out the study meant finding lonely people, isolating them -- and giving them a cold.

A total of 159 people between ages 18 and 55 were assessed for their psychological and physical health, given cold-inducing nasal drops and quarantined for five days in hotel rooms.

Those who were screened in advance for their level of loneliness and became infected reported a greater severity of symptoms than those recorded in previous studies used as controls. 

The size of the participants' social networks appeared to have no bearing on how sick they felt.

The findings are an incentive to be more socially active, leRoy said.

"If you build those networks -- consistently working on them and your relationships -- when you do fall ill, it may not feel so bad," she added.