Kristan Amendola, Laura Harris, Rivka Ohayon, Alison K Shea, Anthea Christoforou, Antony D Karelis, Jennifer J Heisz
The present study utilized a randomized crossover design to compare the short-term effects of time-restricted feeding (TRF) and alternate-day fasting (ADF) on the subjective experiences of young females. Twenty-three females (Mage = 18.3 ± 0.4 years) participated in this study. Participants were asked to complete three days of TRF and three days of ADF, separated by a four-day washout period. On the day before fasting and on each fasting day, the participants completed an online questionnaire at noon. The questionnaire collected information on mood, hunger, diet satisfaction and subjective sleep quality. Total mood disturbance increased following ADF compared to TRF [condition x time interaction: F(3, 57) = 3.35, p = .03, η²ₚ = .15], but this effect disappeared by the second fasting day. Hunger increased on fasting days following both TRF and ADF [main effect of time: F(3, 57) = 19.82, p < .001, η²ₚ = .51, and a condition x time interaction: F(3, 57) = 10.08, p < .001, η²ₚ = .35]. Diet satisfaction was significantly higher during TRF than ADF [main effect of condition: F(1, 19) = 5.21, p = .03, η²ₚ = .22]. Neither fasting protocol significantly affected subjective sleep quality. Together, these findings suggest that TRF may offer a more tolerable fasting strategy than ADF, particularly in terms of mood and diet satisfaction, without adverse effects on subjective sleep quality.