Our biological clocks regulate when we sleep, when we wake up and when we get hungry.
But at a lab at Northwestern University in Chicago, the mice are eating when it should be sleeping.
Researchers, led by neurobiologist Joe Bass, Ph.D., found that as little as a week of eating a high fat diet disrupted mice's body clocks.
Bass says, "It would be as if you went to sleep at night, but an hour later you woke up and went down to the refrigerator and started to eat. You went back to sleep and two hours later, you went back to the kitchen again."
Bass's team at Northwestern University fed some mice regular chow, while others got the equivalent of a "fast-food" diet.
They monitored the animals' sleep, activity and eating behaviors around the clock, and also studied when their body clock genes were switched on and off.
To their surprise, the high-fat diet altered these genetic switches.
Bass says, "So it would be as if the clock hands are stuck in one position and are only sort of, in a very erratic and abnormal way, advancing around the 24-hour cycle."
Mice are nocturnal, but their day and night cycles are controlled by the same genes as peoples'.
Bass says other researchers searching for treatments for obesity and metabolic syndrome might do well to watch the clock.
His work is already attracting attention from the government, and drug companies.
