Nutrient Intake Among Female Shift Workers in a Computer Factory in Japan

Based on a 4-day questionnaire survey for all meals and snacks consumed by female workers in a computer factory in Japan, consisting of 44 daytime workers and 93 weekly-rotating shift workers (of whom 47 and 46 were engaged in, respectively, early-shift work and late-shift work during the survey week), the present study aimed to clarify the effects of shift work on their nutrient intakes in association with food consumption patterns. Their dietary intakes for 3 working days and an off day were assessed by self-registered food consumption records with the aid of a photographic method, and intakes of energy, protein, fat, carbohydrate, calcium and iron were estimated. The inter-group differences were prominent in the working days. The shift workers, particularly the late-shift workers, took smaller amounts of energy and nutrients than the daytime workers, implying that the former group's nutritional status has been worsened, judged from the recommended dietary allowance for Japanese. Their inadequate nutrient intake was due to lower meal frequency and poor meal quality, both of which were conditioned by shift work.