Brigham and Women's Hospital (BWH
) researchers and collaborators from Tufts University and the University of Murcia
found that whether dieters ate main meals early or late influenced significantly the amounts of weight they lost.
Their study was published
on January 29, 2013 in the advanced online edition of the International Journal of Obesity.
Although previous animal studies have demonstrated a link between the timing of feeding and effective weight regulation, so far few human studies have evaluated the importance of when eating occurs in treating obesity, according to the researchers.
Senior author BWH neuroscientist Frank Scheer stated
This is the first large-scale prospective study to demonstrate that the timing of meals predicts weight-loss effectiveness. Our results indicate that late eaters displayed a slower weight-loss rate and lost significantly less weight than early eaters, suggesting that the timing of large meals could be an important factor in a weight loss program.
For this study the teams tracked 420 overweight participants in Murcia, Spain for a 20-week weight-loss treatment program, who self-selected placement into a late-eater or early-eater group, based on their preferred timing of lunch (the main meal for this Mediterranean population), which provided 40 percent of the total daily calories. The early-eating group ate their large lunch before 3 p.m. and the late-eating group after.
The results showed the timing of smaller meals or snacks did not affect outcomes, but the early-eaters lost significantly more weight more rapidly than the late eaters, and late-eaters exhibited a risk factor for diabetes, lower estimated insulin sensitivity
The two groups measured about the same for other known factors affecting weight loss, according to the researchers, such as appetite hormone levels, sleep duration and calorie intake and expenditure.
Lead author University of Murcia physiologist Mara Garaulet concluded
This study emphasizes that the timing of food intake itself may play a significant role in weight regulation. Novel therapeutic strategies should incorporate not only the caloric intake and macronutrient distribution, as it is classically done, but also the timing of food.
But tweaking the timing of patients' eating is a treatment some doctors have already begun adding to obesity therapies, as this video shows.