Fat and Lazy - Is Junk Food to Blame?

A new study finds that junk food may not only make you fat, it could also make you lazy.

Researchers fed junk food to a group of rats. Another group of rats were giving unprocessed foods. After three months, researchers say the group on the junk food became obese. The group on unprocessed foods did not gain weight.

The other part of this research looked at the rats' activity levels after eating.

When investigators gave them a task of pressing a lever to receive a reward, the junk food rats took longer breaks than the lean rats. Analysts believe cognitive impairment may be affected, but not all doctors believe junk food directly leads to laziness. Some think the fat rats were experiencing what's commonly known as a food coma. Their bodies were super tired while trying to digest the fatty food, and bounced back to normal energy levels a few hours after eating.

Doctors say researchers must take a closer look at chemicals in the brain to see if these affects could be long term.