Breakfast: The Key to Unlocking Weight Loss Success?

(Ruddick-Collins et al., 2022)

Observational studies generally show that late eating is associated with an increased risk of obesity, despite the common belief among dietary experts that the timing of calorie consumption does not matter as long as the total number of calories is controlled.

In this 4-week randomized crossover trial, 30 participants with overweight or obesity were assigned to one of two diets that differed only in the distribution of calories consumed at breakfast, lunch, and dinner. The “morning-loaded” group consumed 45% of their daily calories at breakfast, 35% at lunch, and 20% at dinner, while the “evening-loaded” group consumed 20% of their daily calories at breakfast, 35% at lunch, and 45% at dinner.

The primary outcome was change in body weight, and the secondary outcomes included measures of energy expenditure, physical activity, subjective appetite, and metabolic health parameters.

Both groups lost body weight, with no significant difference between the groups. However, the morning-loaded group had lower average hunger and appetite scores and higher levels of satiety-enhancing gut hormones after the breakfast test meal compared to the evening-loaded group. There were no differences between the groups in terms of total daily energy expenditure or physical activity. The study concluded that the timing of calorie intake does not affect weight loss, but it may have an impact on subjective appetite and satiety.

Reference:

Ruddick-Collins, Leonie C., et al. “Timing of Daily Calorie Loading Affects Appetite and Hunger Responses Without Changes in Energy Metabolism in Healthy Subjects With Obesity.” Cell Metabolism, 4 Oct. 2022, www.cell.com/cell-metabolism/abstract/S1550-4131(22)00344-8.