ABSTRACT
This study aimed to clarify the effect of light exposure during the daytime and nighttime on diet-induced thermogenesis (DIT), which is one kind of energy expenditure, and the contribution of autonomic nervous activities (ANA) to the mechanism behind such effects. We found that the light–dark cycle significantly induced a diurnal rhythm of DIT, with afternoon levels tending to be higher than nighttime levels. By contrast, no such rhythms were observed under constant light or dark conditions. There were also no significant differences in ANA between the light conditions. These findings demonstrate that a diminished light–dark cycle leads to disruption of the diurnal rhythm of metabolism and so the retention of ordinary light–dark cycles may be recommended for health maintenance.
Funding
This work was supported by JSPS KAKENHI Grant Number JP26440262.
Declaration of interest statement
The authors report no conflicts of interest.