As a result, energy saving was found in some households, especially in the family of which all the members accomplished lifestyle shift together with the life of the same rhythm. It was found that lifestyle shift has positive effect on wake-time sleepiness and fatigue recovery. Though, the interpretation of the results requires careful attention because of small number of samples, it is indicated that lifestyle shift contributes energy saving as well as health promotion. Switching from night-oriented lifestyle to morning-oriented lifestyle has priority among measures of global warming in household since it does not cost additionally and accompanies the benefit of health promotion.