Intermittent Fasting or Calorie Counting: Which is better for weight loss?

Digital Desk: As weight-loss plans go, intermittent fasting has become highly appealing. The method promises the freedom to eat what you want, but only within specific windows of time—often just eight hours a day. Unlike traditional diets that demand calorie counting or portion control, intermittent fasting primarily requires dieters to pay attention to the clock. "You have this really simple rule: Eat or don’t eat," says a nutrition researcher. 

This straightforward approach has surged in popularity, becoming a trending topic on social media. But does time-restricted eating, a popular form of intermittent fasting, really aid in weight loss and improve health?

Intermittent Fasting

Intermittent fasting involves rotating between periods of eating and fasting. Experts define it as abstaining from food for at least 14 hours. There are several variations, such as eating every other day, fasting for two days a week, or restricting eating to specific hours daily. The most popular form is time-restricted eating, where all meals are consumed within a 10-hour window or less. For instance, a person might delay breakfast until 10 a.m. or noon and have dinner by 6 p.m. or 8 p.m., abstaining from food outside this timeframe.

The Theory Behind Time-Restricted Eating

The rationale behind time-restricted eating lies in its potential to support the body's circadian rhythm, our internal clock. Extended fasting periods may enhance processes that regulate blood sugar and fat metabolism. Early studies in mice from 2012 suggested health benefits from time-restricted eating, and small human studies indicated potential weight loss and improvements in health markers for those with obesity.

Effectiveness for Weight Loss

Research indicates that time-restricted eating might reduce calorie intake, thereby promoting weight loss. Studies suggest that adults with obesity who limit their eating hours, without focusing on calories, naturally consume 200 to 550 fewer calories per day, leading to a 3% to 5% reduction in baseline body weight. 

However, a significant study published in the New England Journal of Medicine in 2022 tracked 139 people with obesity over a year.

Participants either followed a calorie-restricted diet within a certain time window or ate the same number of calories throughout the day. Both groups lost a similar amount of weight—14 to 18 pounds on average—indicating no significant difference between the strategies. 

"Our data right now suggests that time-restricted eating isn’t any better or worse than cutting calories," the expert noted, adding that the method also does not help burn more calories. However, the simplicity of time-restricted eating might make it more sustainable than traditional diets. "Almost no one likes calorie counting," the expert added.

Safety Concerns

Early clinical trials have deemed time-restricted eating "generally safe," according to a report in the journal Obesity. However, recent research presented at an American Heart Association scientific session suggested that those on an 8-hour time-restricted diet had a higher risk of cardiovascular disease death compared to those who ate over 12 to 16 hours. 

This finding, yet to be published in a peer-reviewed journal, urges caution. Experts advise careful consideration, noting that longstanding evidence links skipping breakfast with cardiovascular disease and death. He recommends consulting healthcare providers before adopting restricted eating, especially if the fasting window extends to midday. "It’s a call for pausing before you just recommend a particular diet," Lopez-Jimenez said.

Intermittent fasting, particularly time-restricted eating, offers a simple and flexible approach to dieting that has captivated many seeking to lose weight and improve health. While initial studies and anecdotal evidence suggest potential benefits, larger and more rigorous studies reveal that the technique may not be superior to traditional calorie-restricted diets.

Moreover, emerging safety concerns highlight the importance of consulting healthcare providers before making significant dietary changes. As with any diet, personal suitability and medical advice are key to ensuring both effectiveness and safety.