When You Eat Matters As Much As What You Eat
May 17, 2012

When You Eat Matters As Much As What You Eat

When you eat might be as important as what you eat when it comes to weight gain. That's the conclusion of a study reported in the Cell Press journal Cell Metabolism published online on May 17th.

A new study shows, when mice on a high-fat diet are restricted to eating for eight hours per day, they eat as much as those who eat around the clock, yet they are protected against obesity and other metabolic ills. The discovery proposes that the health effects of a poor diet may result in part from a mismatch between our eating schedules and our body clocks.

"Every organ has a clock," said lead author of the study Satchidananda Panda of the Salk Institute for Biological Studies. This means at times our livers, intestines, muscles, and other organs will work at peak efficiency and other times  they are somewhat sleeping.


"When we eat randomly, those genes aren't on completely or off completely," Panda said. The principle is just like it is with sleep and waking, he explained. If we don't sleep well at night, we aren't fully awake during the day, so we work less efficiently as a consequence.

Panda's team fed mice either a standard or high-fat diet with one of two types of food access: ad lib feeding or restricted access. This experiment was done in order to find out whether restricted feeding alone–without a change in calorie intake–could prevent metabolic disease.

The time-restricted mice on a high-fat diet were protected from the adverse effects of a high-fat diet and showed improvements in their metabolic and physiological rhythms. They suffered less liver damage and gained less weight. The mice also had lower levels of inflammation, among other benefits.



"The focus has been on what people eat," Panda said. "We don't collect data on when people eat."