Weight loss is not affected by meal timings but hunger is

A new study by a team of researchers from the University of Aberdeen and the University of Surrey has dispelled some previous myths around meal times for weight-loss and “chrononutrtion”.

The research conducted on overweight but otherwise healthy participants in Scotland involved the eating two different sized meals (either big breakfast and small dinner or vice versa) for four weeks. While weight loss, physical activity, calorie intake and baseline metabolism were all monitored.

Previous diet research had suggested that a bigger meal consumed earlier in the day was more effective for weight loss and increased calorie burning by the baseline metabolism due to the body’s circadian rhythms.

However, the new findings challenge this popular assumption – which is very popular in the general public seeking weight loss.

Chrono-nutrition is an emerging field of nutritional science, defined as a : “concept reflects the basic idea that, in addition to the amount and content of food, the time of ingestion is also critical for the well-being of an organism.” (Asher 2015)

Researchers said that having a larger meal in the morning caused participants to alter eating behaviours which in turn they said was responsible for the weight loss and not metabolic effects.

Overall average participant weight loss was almost identical between those who had the bulk of their calories in the evening and those who had a bigger breakfast.

But, the study found that participants consuming the largest meal in the morning reported significantly lower hunger in comparison to those who ate the larger meal in the evening.

Leading the scientists to suggest that a big breakfast may assist with compliance to a weight loss regime through a greater suppression of appetite.

References:

Asher G, Sassone-Corsi P. Time for food: The intimate interplay between nutrition, metabolism, and the circadian clock. Vol. 161, Cell. Cell Press; 2015. p. 84–92. 

Ruddick-Collins, L., Morgan, P., Fyfe, C., Filipe, J., Horgan, G., Westerterp, K., Johnston, J. and Johnstone, A., 2022. Timing of daily calorie loading affects appetite and hunger responses without changes in energy metabolism in healthy subjects with obesity. Cell Metabolism,.