Being bullied during childhood can have long-term effects on a person's health into adulthood, U.S. researchers say, going beyond emotional and social consequences.

People who have been bullied may suffer health issues, such as susceptibility to illness and pain, which goes beyond the known psychological outcomes, says researchers at Duke University's School of Medicine.

Those outcomes can include depression, panic attacks and anxiety disorders, but a new study suggests there are other physical health risks as well.

"Among victims of bullying, there seems to be some impact on health status in adulthood," behavioral science and psychiatry Professor William E. Copeland says. "In this study, we asked whether childhood bullying can get 'under the skin' to affect physical health."

Long-term physical consequences of bullying might be the result of an increase throughout the body of low-grade inflammation.

In the study, data was gathered among 1,420 people who were questioned on their experiences of being bullied and who provided blood samples that were analyzed for biological factors.

The researchers tracked the participants from when they were 9 years old through their teenage years.

Focused on C-reactive protein or CRP, a marker revealing a risk factor for health problems including cardiovascular disease or metabolic syndrome that can be a result of long-term low-grade inflammation.

CRP is one known measure of the stress on a person's body and is considered "a harbinger of health problems down the road," Copeland says.

"Our findings look at the biological consequences of bullying, and by studying a marker of inflammation, provide a potential mechanism for how this social interaction can affect later health functioning," he says.

Although levels of CRP rise naturally during adolescence, the highest levels were found in those children reporting significant bullying by others, levels around 1.4 times higher than their peers.

Highest CRP levels were seen in children with experience of repeated bullying suffered over long time periods or in many physical settings, the researchers said.

"We're pretty confident that this is a bullying effect," Copeland says.

Sticks and stones may, as the saying goes, break your bones but words, it appears, can also indeed hurt you.