When it comes to online social networking, people are more likely to change habits that might affect their health when encouraged to do so by cyber conversations with friends they already know well and with whom they are in close contact, new research suggests.

The finding runs contrary to prior indications that health information gleaned from close-knit online social networks is actually less likely to drive behavioral change, given the likelihood that groups of people who are in frequent contact with each other are likely to exchange repetitive and redundant advice.

Older people prefer to read negative news stories about the young, possibly because it makes them feel better about themselves, a new study suggests.

"The more time they spent with negative news about young people, the higher self-esteem they reported. They may get some self-esteem boost out of this," said study author Silvia Knobloch-Westerwick, an associate professor at Ohio State University's School of Communication.

Over the last 10 years, the percentage of Americans who took at least one prescription drug in the past month increased from 44 percent to 48 percent, says a federal government study released Thursday.

Use of two or more drugs increased from 25 percent to 31 percent, and the use of five or more drugs increased from 6 percent to 11 percent, according to the analysis of data from the National Health and Nutrition Examination Survey (NHANES).

The mystery of why some people are more likely to become addicted to opioid painkillers has been partially unraveled by the Geisinger Health System in Pennsylvania.

Its researchers found that the group most vulnerable to addiction has four main risk factors in common: age (being younger than 65); a history of depression; prior drug abuse; and using psychiatric medications. Painkiller addiction rates among patients with these factors are as high as 26 percent.

As the provisions of the Affordable Care Act begin to be implemented, many small businesses in the United States will be able to take advantage of new tax credits, a new report shows.

During the first phase of the act, some businesses employing some 16.6 million workers will be eligible for these tax credits, according to the report released Thursday from the Commonwealth Fund.