Lead author of the study, Courtney Peterson, Ph.D., Pennington Biomedical Research Center, said,
‘Early time-restricted feeding (eTRF) improved metabolic flexibility, which is the body’s ability to switch between burning carbohydrates and fats.
"We found that eating between 8 am and 2 pm followed by an 18-hour daily fast kept appetite levels more even throughout the day, in comparison to eating between 8 am and 8 pm, which is what the median American does," said Peterson.
The study suggests that eating a very early dinner, or even skipping dinner, may have some benefits for losing weight.
The body's internal clock and metabolism are at their optimal functioning in the morning. Thus, eating during the day can have a positive influence on health
The study was the first to test eTRF in humans to aid in weight loss. The study was based on rodent studies which previously found that eTRF reduced fat mass and decreased the risk of chronic diseases.
The current study involved eleven men and women with excess body weight. The participants were followed over four days of eating between 8 am and 2 pm (eTRF) and four days of eating between 8 am and 8 pm. All the participants followed both the eating schedules, same calorie intake and testing to eliminate subjectivity.
The researchers tested the impact of eTRF on calories burned, fat burned and appetite. The findings showed that eTRF reduced daily hunger swings and increased fat burning during several hours at night.
It did not affect how many calories participants burned. The researchers also found that eTRF improved metabolic flexibility, which is the body's ability to switch between burning carbs and fats.
Whether eTRF helps with weight loss or improves other aspects of health is still unknown.
"These preliminary findings suggest for the first time in humans what we've seen in animal models - that the timing of eating during the day does have an impact on our metabolism," said Dale Schoeller, Ph.D., FTOS spokesperson for The Obesity Society and Professor Emeritus at the University of Wisconsin. "With additional research on early-time restricted feeding on humans, we can create a complete picture of whether this innovative method can best help prevent and treat obesity
The research was funded by a TOS Early Career Research Grant awarded in 2014. The findings of the study were presented at The Obesity Society Annual Meeting at ObesityWeek 2016 in New Orleans, Louisiana.