Researchers looked at data from nearly 2,000 randomly chosen people to determine if their circadian or biological clock rhythm (chronotype) affected what they ate and at what time. Clear differences in both energy and macronutrients between the two chronotypes abound, with morning people making healthier choices throughout the day. Evening types ate less protein overall and ate more sucrose in the morning. In the evening, they ate more sucrose, fat and saturated fatty acids.