The concept of farmers markets at hospitals is not entirely new, but it has started to spread -- to places like Mount Sinai Medical Center in New York, University of California San Francisco Medical Center in California, and the Vanderbilt Medical Center in Nashville, Tennessee, which opened its farmers market in May.

CNN: Farmers markets bloom at hospitals

Now scientists - at the University of California, San Francisco, and Cincinnati Children's Hospital Medical Center - believe that body-penetrating light can alter the development of the eye, at least in mice.

BBC: Light in womb 'gives healthy eyes' - in mice

The trial was run at three hospitals: Vanderbilt University Medical Center in Nashville, the Children's Hospital of Philadelphia and the University of California, San Francisco.

CNN: Study: Major benefits for spina bifida surgery in the womb