Objective: Whether a high-protein (HP) diet promotes body weight loss (BWL) when compared with a low-protein (LP) diet is still unclear. Therefore, we evaluated the effects of an HP diet on BWL during postpartum.
Methods: A food-frequency questionnaire with 81 items was applied at 6 mo after delivery to evaluate the diet of 430 postpartum women aged 18-45 y. Body weight was measured approximately at 0.5, 2, 6, and 9 mo after delivery. Body weight loss was modeled by comparing an HP diet (> or =1.2g . kg(-1) . d(-1)) with an LP diet (<1.2g . kg(-1) . d(-1)) using mixed-effects linear regression models adjusted for energy intake, percentage of body fat at baseline, stature, age, race, smoking, and schooling.
Results: Usual energy intake was higher in the HP than in the LP diet group (2623 versus 1791kcal, P<0.0001). Daily mean protein intakes were 1.54+/-0.32g . kg(-1) . d(-1) for the HP group and 0.83+/-0.20g . kg(-1) . d(-1) for the LP group. A multivariate model showed that women in the HP group lost 316+/-0.062g of body weight more per month (P<0.01) when compared with the LP group.
Conclusion: A reported higher protein intake may improve moderate postpartum body weight loss. Further studies should evaluate the long-term consequences of an HP diet postpartum.