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Could eating within our bodies’ natural internal schedule be the key to maintaining a healthy weight and fighting epidemics like diabetes?  Scientists are studying the effects of Time Restricted Feeding (TRF) and the results are promising.

Biologist Satchin Panda of the Salk Institute in San Diego is examining the relationship between our bodies’ circadian rhythm, food consumption, and certain health problems like diabetes, high blood pressure, heart disease, and cancer.  Panda argues that humans are naturally programmed to eat between the hours of sunrise and sunset and sleep during hours of darkness.  He believes that modern society’s 24-hour schedule of electric lighting, instant everything, all hours fast food, and longer work hours and commute are at odds with our natural rhythm and are causing us to eat from early morning until late at night, and this is the reason certain health ailments are on the rise.

Panda noticed that throughout the course of a day, hundreds of genes in the livers of mice turned on and off cyclically.  As the liver is largely responsible for metabolizing calories, and the discovery that most of these genes were tied to eating and digestion, Panda wanted to see what would happen if mice were fed only during certain hours, compared to mice that could eat all day. 


In the study, the same number of calories were available to two separate groups of mice.  One group was allowed to eat at anytime throughout the day, the other group was restricted to an 8-hour window of feeding.  After four months, the 8-hour feeders weighed 28 percent less than the anytime mice.  The researchers were amazed by this and repeated the study three more times, all with the same results.

Further, the time restricted mice showed normal blood sugar levels and could run twice as long, while the anytime mice developed Type 2 diabetes.  Research also showed a reduced risk of cancer and heart disease for the TRF mice.  It should be noted there are some key differences in the bodies of mice and humans, and further research is needed before scientists can definitively say the TRF approach will work for all humans.

Still, other studies are showing some positive human correlations.  In a University of Alabama at Birmingham study of men with pre-diabetes, a condition where blood work is showing signs of them approaching development of full diabetes, the participants were given prepared meals and allowed to eat between 8 a.m. and 2 p.m. and later, 8 a.m. and 8 p.m.  The group showed significantly lower blood pressure and improved insulin sensitivity on the 6-hour feeding schedule compared to the 12-hour schedule.

Panda also looked at the eating habits of 156 people.  More than half reported consuming food over a 15-hour period or longer, while only 10 percent consistently ate during only a 12-hour window.  He took a small sampling of these participants, people who were overweight and typically ate during 14-hour periods throughout the day.  When these subjects were limited to 10-hour feeding times for four months with no other restrictions—the study participants could eat whatever they wanted—they lost weight, had more energy, and slept better.

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Can the TRF approach work for you?  It might if you find you are hitting a wall in your quest to reach a healthy body composition.  Take a look at your eating schedule over several days or even weeks.  Figure out your daily average hour range in which you eat.  If your eating window is longer than 12 hours, consider shortening it.  Most people who have had success on this program have eating windows of 6-10 hours.  Eat all of your fuelings during this time window.  Give yourself several months to evaluate the results.

While the research into the long-term effects of TRF is in its infancy, what is clear is that obesity, cancers, heart disease, diabetes, and high blood pressure are on the rise in our society.  Likely the modernization of our culture and the instant availability of less than healthy food choices are contributing to this epidemic.  If we can see a positive change just by changing when we eat, imagine what may be possible by modifying what we eat as well.  Have you had success with a type of time restricted feeding?  Tell us about it in the comments.