No diet or sports: the small change in eating habits that will keep you from gaining weight

The journal "Cell Metabolism" recently published a study that revealed that eating later in the day can directly affect our biological weight regulation in three main ways. These include the number of calories we burn, our hunger levels and how our bodies store fat.

"We wanted to test mechanisms that might explain why eating late may increase the risk of obesity," neuroscientist Frank Scheer said in October when the study was published. "Our previous study showed that eating late is associated with an increased risk of obesity and increased body fat content and poor weight loss success, we wanted to understand why."

The study was strictly controlled, and included 16 participants with a body mass index (BMI) in the overweight or obese range.

Each volunteer went through two different six-day experiments, with their sleep and food intake controlled, and several weeks passed between each test.

In one experiment, participants followed a strict schedule of three meals a day at fixed times – breakfast at 09:00 in the morning, lunch at 13:00 in the afternoon and dinner around 18:00 in the evening.

In the second experiment, the three meals were alternated, with the first eaten around 1:00 PM and the last around 9:00 PM.

Using blood samples, survey questions and other measurements, the team was able to make several observations, from which it emerged that when eating later, levels of the hormone leptin – which tells us when we are full – were lower over the course of 24 hours, suggesting that the participants felt hungrier. Furthermore, the calories were burned at a slower rate.

Tests have also shown that adipose tissue gene expression—which affects how the body stores fat—increases lipogenesis, which builds adipose tissue, and decreases lipolysis, which breaks down fat.

"We isolated these effects by controlling for confounding variables such as caloric intake, physical activity, sleep and light exposure, but in real life, many of those factors may be affected by meal timing," Scheier said.

The conclusion that emerged from the study was that eating early before 6:00 PM at regular times will prevent obesity, which can lead to other health problems, including diabetes and cancer.

The study shows that eating earlier in the day can affect three key factors in how energy is balanced and the risk of obesity, a change that may be easier to implement for some people than strict diet or exercise.