A 12-week programme of time-restricted eating may help people maintain weight loss for up to a year, according to a new study published in Clinical Nutrition. Researchers found that participants who limited their daily eating to an eight-hour window were more successful at keeping weight off than those who received standard nutritional advice alone.

The secondary analysis examined data from 99 adults aged between 30 and 60 who were living with overweight or obesity. Researchers assigned participants to one of four eating patterns: an early eight-hour eating window beginning before 10:00, a late window starting after 13:00, a self-selected eight-hour window, or their usual eating schedule. All participants also received guidance on following a Mediterranean-style diet and increasing physical activity.

After the 12-week intervention ended, researchers did not instruct participants to continue or stop their assigned eating schedules. One year later, they assessed body weight, body composition and eating habits to determine whether the effects had lasted.

The findings showed that participants in both the early and late time-restricted eating groups maintained greater weight loss than those in the control group. Researchers also found that all three time-restricted eating groups sustained lower neck circumference, while the late eating group maintained larger reductions in waist and hip measurements.

However, the study also raised concerns about the loss of fat-free mass, which includes muscle tissue. Researchers observed reductions in fat-free mass in several fasting groups, suggesting that some of the weight loss came from lean body tissue rather than fat alone.

The research team said the benefits appeared regardless of whether participants ate earlier or later in the day, indicating that shortening the daily eating window may be more important than the specific timing of meals.

The authors suggested that time-restricted eating could be an effective long-term strategy because it is relatively simple to adopt and restart if weight begins to return.

Despite the promising results, the researchers acknowledged several limitations. Only 65 of the original 99 participants completed the one-year follow-up, and the study involved participants from a single research centre. Some information also relied on self-reporting through a mobile application, which may have influenced the findings.

Independent experts said larger studies with longer follow-up periods are needed to confirm the long-term benefits and identify any potential health risks. They also stressed that people following intermittent fasting should focus on preserving muscle mass by consuming enough protein and including resistance exercise in their routine.

The researchers concluded that time-restricted eating could become a practical lifestyle approach to help people maintain weight loss after completing a structured weight management programme. However, they advised that anyone considering intermittent fasting should consult a qualified healthcare professional to ensure the approach is suitable for their individual health needs.