Physiology

You Are When (Not What) You Eat

+ See all authors and affiliations

Science  08 Jun 2012:
Vol. 336, Issue 6086, pp. 1211
DOI: 10.1126/science.336.6086.1211-b
CREDIT: THINKSTOCK

Mammals synchronize their metabolism with daily cycles of eating and activity, and disruption of such patterns has deleterious effects on metabolism. Hatori et al. explored whether such disruption may affect diet-induced obesity in mice. Mice are nocturnal, so they normally have peaks of food intake, activity, and energy expenditure during the night. Mice allowed unlimited access to a high-fat diet, however, had blunted rhythms, fasted for a shorter time, and ate during a greater proportion of the day. They also got fat and showed signs of metabolic disease. However, when the authors controlled the timing of eating so that the mice on the high-fat diet ate only during the night, they ate as much as the unrestricted animals did, but did not become obese, retained sensitivity to insulin, and avoided hepatic steatosis and inflammation that plagued the fat mice. Restricted food consumption in tune with the circadian cycle may have inhibited gluconeogenesis and instead favored glycolysis, reduction of glutathione, and anabolic processes. Whether such results will also apply to humans remains to be determined, but changing when you eat rather than what you eat may be a lot easier to implement.

Cell Metab. 15, 10.1016/j.cmet.2012.04.019 (2012).

Navigate This Article