Sequential diets and weight loss: Including a low-carbohydrate high-fat diet with and without time-restricted feeding.

Objective: The aims of this study were to assess the effectiveness of a low-carbohydrate high-fat (LCHF) diet with and without a time-restricted feeding (TRF) protocol on weight loss and participating in three sequential dietary interventions (standard calorie-deficit diet, LCHF, and LCHF + TRF) on weight loss outcomes.

Methods: Data from 227 adults from the Wharton Medical Clinic (WMC) were analyzed using a unidirectional case crossover design. Data was imputed for 154 patients to create a pseudo-sample in which everyone participated in three dietary interventions: standard calorie restriction, LCHF, and LCHF + TRF.

Results: Patients lost an average of 11.1 ± 1.3 kg (9.8 ± 1.1%) after three sequential dietary interventions (P < 0.0001). Patients lost a statistically significant amount of weight from the standard WMC, LCHF, and LCHF+TRF diets (P < 0.05). With and without adjustment for age, sex, body mass index at the start of the dietary protocol, and treatment time, patients lost a similar amount of weight regardless of the dietary intervention (P > 0.05). Approximately 78.6% of patients achieved ≥5% weight loss with at least one of the diets.

Conclusion: Patients can lose a similar amount of weight regardless of the diet they are following. Approximately 78.9% of patients achieved 5% weight loss with at least one of the diets and lost an average 11.1 kg (or 9.8%). This is nearly double what has been previously reported for one dietary intervention. Thus, participating in sequential diets may be associated with greater absolute weight loss, and likelihood of achieving a clinically significant weight loss.