Washington (SmartAboutHealth) - A new study has found a link between feeling lonely and stressed-out, and having an increased risk of breast cancer.

The study was led by Gretchen Hermes from Yale University in New Haven, Connecticut, and focused figuring out whether loneliness could attribute to the development of breast cancer.

The researchers divided rats up into different groups. Some of the rats were taken away from a social group after they were born, causing them to feel lonely and stressed, while others were left in the social atmosphere.

What they found was that the lonely rats were three times more likely to develop breast cancer tumors.

They also found that the rats who were lonely were far more likely to develop tumors that were considered to be deadly breast cancer tumors.

The feeling of being lonely and stressed is what is believed to cause this imbalance in the body that increases the risk of developing the terrible disease.

This is not the first study to link loneliness to poor health, but it is the first to link loneliness to breast cancer.

The study has been published in the journal Proceedings of the National Academy of Sciences.