Are you one of the many people who often end up eating later at night? A new study sheds light on how this habit may actually be detrimental.
Eating late at night is a no-no for many diets, but not many studies have delved into its actual effects on the three key factors in regulating body weight, Brigham and Women’s Hospital noted in a news release. These are “regulation of calorie intake, the number of calories you burn, and molecular changes in fat tissue.”
For their new study, published Tuesday in Cell Metabolism, researchers had a look at the effects of early eating compared to late eating, while controlling for other important factors such as light exposure, sleep and physical activity.
“In this study, we asked, ‘Does the time that we eat matter when everything else is kept consistent?'” study’s first author, Nina Vujovic of Brigham’s Division of Sleep and Circadian Disorders, said in the news release.
To find out, the researchers conducted the study on 16 participants who are considered either overweight or obese. They completed two laboratory protocols — the early eating protocol and the late eating protocol — wherein the meals were delayed by 240 minutes (4 hours). They also had fixed sleep and wake schedules for two to three weeks prior to the lab protocols, and also followed strict diets at home in the three days leading up to it.
While in the lab, participants documented their hunger and appetite. Important samples such as blood samples, body temperature, energy expenditure and adipose tissue biopsies, were also collected.
The researchers found that late eating affected all three main factors. It “doubled the odds of being hungry,” burned calories slower and actually altered the mechanisms behind lipid metabolism.
“(W)e found that eating four hours later makes a significant difference for our hunger levels, the way we burn calories after we eat, and the way we store fat,” said Vujovic.
“Our results show that late eating consistently altered physiological functions and biological processes involved in regulation of energy intake, expenditure, and storage—each of these three in a direction favoring weight gain,” the researchers wrote.
And in the real-life setting wherein there is better food availability, the researchers believe the effects of late eating “may be even more pronounced.”
This shows the various factors by which late eating may increase obesity risk, they added. It also adds to the body of research on just how meal timings may actually affect people. In a recent study, for instance, researchers also found that those who had meals both in the daytime and nighttime had increased depression-like and anxiety-like mood levels.
In the case of the current study, researchers noted that further studies are needed to test its “generalizability.” For instance, there were only five female participants, leading to an underrepresentation of the sex.