Researchers have found that graphic anti-smoking images may be more powerful than words alone in warning people from different income and racial groups about the dangers of smoking.

The study, from the Legacy Foundation and the Harvard School of Public Health, finds that bold pictorial cigarette warning labels approved by the Food and Drug Administration depicting health consequences of smoking can impact on smokers' intentions to quit. (Legacy's mission is to reduce tobacco use in the U.S.)

About 3,300 adult smokers from diverse racial, ethnic and income groups were recruited to take part in the study. Some received written warnings about the dangers of smoking while others received highly graphic images showing possible consequences, including blackened lungs, cancers, even death. The study appears in the online journal, PLOS One.

Those who saw the images reported being more upset, scared and motivated to quit than those who saw written warnings alone. That reaction was similar across racial and economic groups. That's an important finding, the researchers say, since certain minority and low-income groups have significantly higher rates of smoking than the general population.

"The implementation of graphic warning labels appears to be one of the few tobacco control policies that has the potential to reduce communication inequalities across groups," Jennifer Cantrell, assistant director for research and evaluation at Legacy and lead author of the study, said in a statement.

About 20 percent of the general adult population smokes. But one third of the population below the federal poverty level smokes, according to Legacy.

A federal law requiring such graphic warnings on cigarette packs was blocked last year when tobacco companies argued it violated their first amendment rights. The government is now appealing that decision to the Supreme Court. It's not clear if the high court will hear it.

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