Shiftwork & Nutrition

The biological clock modulates physiological processes in the human body as a function of time. Human function is defined by activity during day time and inactivity during nighttime. For instance, at night the digestive system is in a resting state and functions like stomach and intestinal peristalsis, production of gastric juices and insulin are diminished compared to day time. As a result, shiftworkers who frequently work during night time (1,1 million in the Netherlands, CBS 2010) are less able to tolerate and digest food. The relationship between shiftwork, nutrition and health has been extensively studied; specifically the mechanisms of the Shiftwork Metabolic Syndrome (SMS). SMS includes gastrointestinal symptoms (bloating, gas, constipation), overweight and diabetes type 2 . Fewer studies have been conducted so far investigating the relationship between the composition of meals and fatigue, known as one of the primary safety risk factors of night work. For example, changes in the protein/carbohydrate ratio of meals (more protein and fewer carbohydrates) were related to an improvement in alertness and cognition. Apart from meal composition, meal frequency also determines employee performance during the night shift. The primary goal of this project is to extensively research the cognitive and behavioural responses to nutrients and meal structure as a function of time-of-day. The results could lead to nutrition guidelines that contribute to improvement of alertness and performance in shiftworkers.