By: Iris Xu

If you’re tired of counting calories and restricting your food choices, researchers recently discovered that there may be a simpler way to lose weight: watching the clock. According to a yearlong study published in the Annals of Internal Medicine, people who practiced time-restricted eating achieved significant and sustained weight loss, comparable to those who closely monitored their calorie intake.

The study, conducted by researchers at the University of Illinois Chicago, compared two weight-loss methods: calorie reduction and time-restricted eating. Both groups of dieters lost approximately 4% of their body weight after a year, while the control group gained about 1%. However, the study showed that time-restricted eating is an easier diet to adhere to than calorie reduction. This study is the first in the United States to directly compare these two approaches.

According to the Los Angeles Times, in the United States, the prevalence of obesity is a major concern, with nearly 42% of Americans aged 20 and older are classified as obese. Obesity is associated with various serious health conditions, including heart disease, type 2 diabetes, and certain types of cancer. Additionally, obesity significantly increases healthcare costs, with obese individuals paying approximately $2,500 more for medical care each year.

Traditional weight loss methods often involve planning precise low-calorie meals and closely monitoring portion sizes, which can be both time-consuming and expensive. It also requires a high level of discipline to resist temptation in various social situations. In recent years, time-restricted eating has gained popularity as an alternative weight-loss strategy. The concept is to restrict your eating window to six or eight hours a day, which helps reduce insulin production and calorie intake.

The study by the University of Illinois researchers involved 90 obese participants, who were randomly assigned to one of three groups. The first group limited their eating to the hours between noon and 8 p.m., fasting for the remaining 16 hours. The second group reduced their daily caloric intake by 25%, approximately 500 calories on average. The third group maintained their usual eating and exercise habits as a control.

After six months, the time-restricted eating group lost an average of 8.8 pounds, while the calorie reduction group lost an average of 11.2 pounds. Although the difference between the two groups was not statistically significant, both groups achieved substantial weight loss compared to those in the control group, who gained weight over the year.

During the second six months, participants focused on weight maintenance. The time-restricted eating group expanded their eating window to 10 a.m. to 8 p.m., while the calorie reduction group adjusted their caloric intake to maintain their weight. After a year, the time-restricted eating group remained 7.7 pounds (3.5 kilograms) lighter, and the calorie reduction group maintained a weight loss of 9.5 pounds (4.3 kilograms), both significantly better than the control group.

The study primarily included women, Black, and Latino participants. Although it is uncertain at this stage in the research, whether similar results would occur in overweight individuals who are not obese. The lead researcher, Krista Varady, believes that time-restricted eating may still be effective, although potentially to a lesser extent.

Varady emphasizes the simplicity and accessibility of time-restricted eating, as it does not require purchasing expensive products or extensively modifying your pantry. All that is needed is to determine a specific time window for eating and sticking to it as much as possible.