Mice fed at the ‘wrong’ time gained twice as much weight even though they ate the same amount

By Larry Hobbs
Tuesday, September 08, 2009

Mice fed at the “wrong” time gained more than twice as much weight as those fed at the “right” time even though their calorie intake and level of activity was the same.

This according to a study from researchers at Northwestern University in Evanston, Illinois.

The strain of mice they used are “nocturnal, being more active and consuming most of their calories (80%) during the dark phase”.

Right Time Feeding

Mice fed at the wrong time gained 20%

When they were fed during the 12 hours that they normally eat, that is, the “right” time, the mice gained roughly 20% of their body weight during the 6-week study, going from roughly 22.5 grams to 27 grams (data guessed at from Figure 1 in the paper).

Wrong Time Feeding

Mice fed at the right time gained 45%

However, when mice were fed during the 12 hours that they do not normally eat, that is, the “wrong” time, the mice gained roughly 45% of their body weight, going from roughly 22 grams to 32 grams (data guessed at from Figure 1 in the paper).

Mice and Diet

Mice were 9-weeks-old and fed a 60% high-fat diet

The mice were 9-weeks-old when the study began and were fed a 60% high-fat diet.

Sleep

No difference in sleep between mice

“Sleep restriction or poor sleep quality could also be leading to weight gain, although our preliminary data indicate no overall sleep differences between light- and dark-fed mice,” the authors noted.

Other Research

Non-breakfast eaters and those with night-eating syndrome tend to be heavier

Other research shows that “non-breakfast eaters or patients with night-eating syndrome” tend to be heavier the paper also notes.

Studies have also found that people who circadian rhythms are interrupted have higher blood sugar and insulin levels.

Conclusion

Eating at the ‘wrong’ time can lead to weight gain

“These findings, taken together with the present results indicate that the synchrony between circadian and metabolic processes plays an important role in the regulation of energy balance and body weight control,” the authors concluded.

“Importantly, this study is the first to show causal evidence that feeding at the ‘wrong’ time can lead to weight gain.”

REFERENCE

Arble D, Bass J, Laposky A, Vitaterna M, Turek F. Circadian timing of food intake contributes to weight gain. Obesity (Silver Spring). 2009 Sep 3, published early on-line.

AUTHOR’S CONTACT INFORMATION

Fred W. Turek, PhD
Center for Sleep and Circadian Biology
Northwestern University
Evanston, Illinois, USA
(847) 491.2865 phone
(847) 491.5211 fax
http://www.northwestern.edu/neurobiology/faculty/turek.html
fturek@northwestern.edu

Charles & Emma Morrison Professor
Director of the Center for Circadian Biology & Medicine
Faculty, Dept. of Psychiatry & Neurology, Feinberg School of Medicine