Intermittent fasting has gained widespread attention in recent years as a viable alternative to traditional weight loss methods, such as calorie counting, which can be burdensome and difficult to maintain for many individuals.

There are various ways to practice intermittent fasting, with time-restricted eating being a popular method. This approach involves restricting your food intake to a specific time frame, typically ranging from six to eight hours per day.

Studies indicate that this approach may lead to weight loss in the short term by reducing overall calorie intake due to eating less food. However, its effectiveness over a longer period of time has been less clear.

A recently released study could provide some insight.

Krista Varady, a professor of nutrition at the University of Illinois Chicago and a leading researcher in the field of intermittent fasting, recently conducted a study to determine whether people can successfully lose weight and maintain their weight loss over the course of a year.

Study: Intermittent Fasting Comparable to Counting Calories

According to Varady’s study, intermittent fasting can be an effective method for weight loss and weight maintenance over a 12-month period, with outcomes comparable to those of calorie counting. The clinical trial’s findings were published in the Annals of Internal Medicine.

The weight loss was not substantial, only around 5% of total body weight, but the results are promising for experts in the field because they suggest that individuals can maintain this habit over an extended period.

According to Courtney Peterson, a professor of nutrition at the University of Alabama at Birmingham who was not part of the study, the findings are quite exciting. She believes that the research suggests people can maintain this diet for an extended period, unlike a fad diet where individuals might follow it for a short time before reverting to their old eating habits.

Varady’s team selected 90 individuals with obesity (defined as a body mass index above 30) from the Chicago area and divided them into three groups: One group was restricted to eating only between noon and 8 p.m., another group was required to count calories and reduce their daily energy intake by 25%, and the third group maintained their usual eating habits.

Following a six-month period of weight loss, the individuals involved in the study entered a phase focused on maintaining their weight. This was achieved by increasing the time frame for eating from eight hours to 10 hours in the intermittent fasting group, while simultaneously raising the daily caloric intake for the calorie restriction group.

According to Varady, the study was structured in such a way to account for the common phenomenon where individuals tend to experience weight loss for approximately six months while following a diet, after which their progress tends to level off.

Counting Time Almost Equal to Counting Calories

The research revealed that individuals who practiced time-restricted eating experienced an average weight loss of approximately 10 pounds greater than those in the control group, while those who tracked their calorie intake lost around 12 pounds more. However, the difference in weight loss between the two groups was not statistically significant.

According to Varady, the main idea is that you can attain similar energy restriction by focusing on time counting rather than calorie counting.

Intermittent fasting has been studied previously, and the findings showed that individuals who restrict their calorie intake and limit their eating to an eight-hour window experience comparable weight loss over the course of a year as those who only limit their calorie intake without restricting their eating window.

The novel aspect of the recent study is that individuals in the intermittent fasting group were not directed to monitor their caloric intake, yet they still managed to decrease their daily calorie consumption by approximately 400 calories, which is comparable to the reduction observed in the calorie-counting group.

Reduce Calories Naturally

According to Varady, the findings indicate that implementing time restrictions on eating can result in a natural reduction in calorie intake. This may be attributed to the reduction of available eating time, particularly during the evening hours when people have less time to eat.

People generally consume their meals within a 12 to 14 hour time frame, so the adjustment made was simply reducing that window by approximately six hours. The main focus was eliminating post-dinner snacking.

According to Peterson, imposing restrictions on your eating schedule can have a positive impact on your snacking habits, potentially leading to less mindless eating in the evening. Additionally, research from her lab suggests that intermittent fasting can influence hormone levels and promote better appetite control.

The study revealed that there was no significant difference in the cardiovascular and metabolic well-being of the two groups that lost weight. Although research indicates that consuming food earlier in the day may have positive effects on metabolic health, Varady’s team opted for a 12-hour eating window (from noon to 8 p.m.) to reflect the typical pattern of time-restricted eating followed by individuals in real-life scenarios.

From a practical standpoint, it’s challenging to imagine many people being able to abstain from eating after 4 p.m. daily. If you’re able to make it work for you or if it aligns with your lifestyle, then it could be a viable option.

Weight Loss Is Sustainable with Support

The study found that regular counseling sessions with dietitians, focused on healthy food choices and cognitive behavioral strategies, may contribute to sustainable weight loss for both weight loss groups.

According to Dr. Adam Gilden, associate professor of medicine at the University of Colorado Anschutz Medical Campus and author of an editorial accompanying the study, the level of support provided in this instance is noteworthy. Gilden points out that the majority of individuals engaging in similar efforts do not have the benefit of structured guidance, be it dietary or behavioral, and are instead relying on their own resources.

He attributes his patients’ struggles with time-restricted eating to this very reason.

Gilden references a separate trial that found no significant weight loss after 12 weeks of time-restricted eating. He notes that this study did not provide participants with dietary guidance or support.

The research suggests that time-restricted eating is as effective as traditional calorie restriction when participants receive support. However, its effectiveness in real-world scenarios without support is uncertain.

In the study, those who did time-restricted eating or calorie counting had “moderately high adherence” throughout the course of the yearlong study.

Throughout the yearlong study period, participants who practiced time-restricted eating or calorie counting showed moderately high consistency in their adherence to the assigned dietary regimens.

Lose Weight with Less Effort

According to Peterson, earlier studies indicate that the effort required for calorie counting, which is often the standard guidance for individuals seeking weight loss, can be challenging to maintain. This involves educating individuals about portion sizes and caloric content of various foods, as well as tracking and logging meals.

She notes that many people may find it to be a significant inconvenience.

According to Peterson, the study’s findings suggest that time-restricted eating can be as effective as traditional calorie counting, yet require less effort, in reducing overall caloric intake.

According to Dorothy Sears, a professor of nutrition at Arizona State University’s College of Health Solutions and executive director of clinical and community translational science, the findings of this research do not suggest that intermittent fasting is an excuse to make poor dietary choices.

She notes that our bodies are programmed to absorb nutrients most efficiently during daylight hours. So in order to maximize health benefits, it’s recommended to consume meals during the daytime and avoid eating at night, as this can lead to adverse health outcomes.

She concludes that there’s no need to engage in a pointless debate about whether calorie counting or time-restricted eating is better than the other, but to focus instead on determining whether time-restricted eating is as effective as calorie counting, and this study demonstrates that it is.