If weight loss wasn't a great enough challenge in itself, sustaining the results can present a whole new hurdle for slimmers.
Now, a new study has found that intermittent fasting leads to successful long-term weight loss, regardless of when the eating window occurs during the day.
The research, presented at the European Congress on Obesity (ECO) 2025, shows that participants who followed an 8-hour eating window maintained their weight loss after 12 months, whilst those with habitual eating patterns regained weight.
The study involved 99 Spanish participants with an average age of 49, all classified as having overweight or obesity.
Sustaining weight loss is one of the biggest challenges in obesity management
GETTYResearchers randomly assigned them to four groups for 12 weeks: a habitual eating window of 12 hours or more, early time-restricted eating (8-hour window starting before 10am), late time-restricted eating (8-hour window starting after 1pm), or self-selected time-restricted eating (8-hour window at the participant's preferred time).
Body weight and waist and hip measurements were recorded at the start, after 12 weeks, and 12 months later.
After 12 weeks, researchers discovered that all time-restricted eating groups lost more weight than those in the habitual eating group.
This finding suggests that time-restricted eating can be an effective strategy for short-term weight loss, even without strict calorie counting.
At the 12-month follow-up, participants in the habitual eating group had regained weight, whilst all three time-restricted eating groups maintained their weight loss.
Dr Camacho-Cardenosa, leader of the study, emphasised the significance of these findings, telling Medical News Today: "Sustaining weight loss over time is one of the biggest challenges in obesity management.
"Many people lose weight initially, but often regain it. Finding new, effective, and pragmatic strategies is crucial."
LATEST DEVELOPMENTS:
Time-restricted eating can be an effective strategy for short-term weight loss
GETTY
She added that her team's next research step is to "explore how time-restricted eating combined with exercise affects cardiometabolic health" and to identify which individuals benefit most from specific eating windows.
Dr Mir Ali, a bariatric surgeon, noted that the timing of eating windows isn't as crucial as the duration of fasting: "[W]hat the study showed is that the time of day is not as important as the amount of time you stay away from eating."
Registered dietitian Monique Richard recommends that those considering intermittent fasting should assess their daily schedule and consider whether they can meet their nutritional needs within an eight-hour window.
She advised being intentional about why, how, what and when we eat.
