As weird as it may sound, the fruits and vegetables in the produce aisle at the grocery store are still alive. So alive, in fact, that they still have "internal clocks" that respond to the environment, according to a new study in the journal Current Biology.
"Vegetables and fruits don't die the moment they are harvested," study researcher Janet Braam, a biologist, professor and chair of the Department of Biochemistry and Cell Biology at Rice University, said in a statement. "They respond to their environment for days, and we found we could use light to coax them to make more cancer-fighting antioxidants at certain times of day."
That's because plants naturally ramp up production of chemicals used to fight off insects before sunrise (which is when bugs tend to feed on plants). But some of these chemicals also hold health benefits for humans.
Researchers found that they were able to control the internal clocks of different fruits and vegetables, including cabbage, spinach, blueberries, lettuce, zucchini and carrots, by exposing them to periods of light and periods of dark -- a period called "entrainment," that researchers likened to recovering from jet lag after experiencing an international time difference.
"We cannot yet say whether all-dark or all-light conditions shorten the shelf life of fruits and vegetables," such as when they're kept in dark refrigerator trucks or storage units, Braam said in the statement. "What we have shown is that keeping the internal clock ticking is advantageous with respect to insect resistance and could also yield health benefits."