New research suggests that early risers may have a healthier diet than night owls.
Published in Obesity, the scientific journal of The Obesity Society (TOS), the research adds to the existing data that "morning type" people may be healthier than "evening type" people, and is the first study of its kind to look at if a person's circadian or biological clock rhythm (chronotype) affected what they ate, and at what time.
Led by Mirkka Maukonen, of the National Institute for Health and Welfare at the Department of Public Health Solutions in Helsinki, Finland, the research used data from 1,854 participants aged 25 to 74 years old taking part in Finland's national FINRISK 2007 study.
The results showed clear difference between the two different chronotypes of morning and evening people, with the team finding that not only did morning people eat earlier in the day than evening people, they also made healthier food choices throughout the rest of the day.
Evening types ate more sucrose, a type of sugar, in the morning and ate more sucrose, fat and saturated fatty acids in the evening. They also ate less protein overall.
The difference was even stronger on weekends, with evening types having more irregular meal times and eating more.
Evening types also slept worse and were less physically active overall.
Commenting on the results and the significance of the new findings TOS spokesperson Courtney Peterson, PhD, of the University of Alabama at Birmingham, said, "Previous studies have shown that eating earlier in the day may help with weight loss and lower the risk of developing diabetes and heart disease. What this new study shows is that our biological clocks not only affect our metabolism but also what we choose to eat."
"Linking what and when people eat to their biological clock type provides a fresh perspective on why certain people are more likely to make unhealthy food decisions," added Peterson.
"Early birds may have an extra advantage over night owls when it comes to fighting obesity as they are instinctively choosing to eat healthier foods earlier in the day."