It has always been a popular tip for people looking to lose weight to avoid late-night snacking.
No wonder, as a body of research has shown that eating late at night is associated with increased body weight and an increased risk of obesity.
But so far, there are few studies that have investigated specifically why late-night eating is associated with increased body weight, and this is what a recent US study set out to uncover, according to the Science Alert website.
The study found that eating four hours later than normal actually altered many of the physiological and molecular mechanisms that lead to weight gain.
This recently published research also confirmed that eating earlier in the day is more beneficial for both appetite and body weight control.
eating late
To conduct the study, the researchers had 16 participants follow two different meal schedules, for a total of six days.
The first protocol had participants eat their meals early in the day, with the last meal eating about six hours and 40 minutes before bedtime.
The second protocol had participants eat all of their daily meals after approximately four hours.
Expressive – iStock
This means that they skipped breakfast and instead ate lunch, dinner and dinner, and then ate their last meal just two and a half hours before bed.
3 different scales
In addition, the study was conducted in a controlled laboratory, and participants in each group ate an identical diet, while eating times for all meals were spaced equally by about four hours between them.
To understand how late eating affects the body, the researchers specifically looked at three different metrics associated with weight gain:
1- Effect of appetite
2- Effect of eating time on calorie burn
3- Molecular changes of adipose tissue
Appetite was measured using two methods. The first was to have participants rate their hunger throughout the day.
The second technique is to collect blood samples to check the levels of appetite-regulating hormones in the participants’ blood, such as leptin (which helps us feel full) and ghrelin (which makes us feel hungry).
These hormones were assessed hourly over a 24-hour period during the third and sixth days of each experiment.
increases hunger
The researchers found that eating late not only increased the subjective feeling of hunger the next day, but also increased the proportion of “hunger” hormones in the blood, despite the participants eating an identical diet in both protocols.
Late eating also reduced the number of calories burned the next day.
feeling hungry expression
In participants who had adipose tissue biopsy, late eating was also shown to cause molecular changes that promote fat storage.
Meanwhile, together, these findings suggested that late eating leads to a number of physiological and molecular changes that, over time, can lead to weight gain.