Morning person or morning curmudgeon? For type 2 diabetes and heart disease, which circadian rhythm works best for you might play a role: People who like to stay up late use fat less well for energy. This poses a risk to weight and metabolism.
Researchers have studied the metabolism of people in the morning and in the evening. Early risers were found to consume more fat for energy than evening people, both at rest and during short, medium- and high-intensity workouts. Early risers were also more insulin sensitive. Evening people, on the other hand, used carbohydrates more for energy, and their bodies had to release more insulin to lower blood sugar levels, the scientists report in the journal Experimental Physiology. The latter indicates a higher risk of type 2 diabetes.
It is not yet known why the metabolism differs according to the daily rhythm. Professor Steven Malin of Rutgers University in New Jersey said: “The differences in lipid metabolism between ‘larks’ and ‘owls’ indicate that circadian rhythms may affect how the body uses insulin. We also found that early risers are more physically active and in better shape than evening people, who tend to be more sedentary throughout the day. »
The researchers divided 51 people into two groups based on their circadian rhythms and measured their body mass and composition using advanced imaging. They looked at metabolism using breath samples. During the study, which took place over one week, study participants followed a controlled diet to minimize the impact of the diet on the results.
What: DOI 10.1113/EP090613