Weight Reduction and Changes in Body Circumferences in Lactating Women as a Function of Differences in Dietary Macronutrient Content.

Objectives: Investigating waist circumference (WC) and abdominal circumference (AC) evolution in lactating women, based on macronutrient intake adequacy up to 6 months after childbirth. Materials and Methods: Prospective cohort comprising lactating women recruited at a maternity hospital in Minas Gerais State, Brazil, from June 2018 to June 2019. Selected individuals were healthy adult women who had given birth 72 hours before data collection. Sociodemographic, breastfeeding, and anthropometric data were collected. Food intake was determined through 24 hours dietary recalls. Adequate carbohydrate, protein, and lipid intake was herein defined as 45-65%, 10-35%, and 20-35% of the caloric value consumed by participants, respectively. Wilcoxon test and generalized estimating equations were carried out. This research was approved by the Research Ethics Committee, as well as by the National Research Ethics Committee. Results: There was decrease in weight (-4.45 kg), body mass index (-4.43 kg/m 2 ), WC (-4.70 cm), and AC (-4.70 cm) values from the baseline ( n  = 260) up to 6 months after childbirth ( p  < 0.001). The evolution of these measurements has indicated that high carbohydrate and low protein intake were associated with the highest AC values. Low protein and high lipid intake have led to lower WC values ( p  < 0.05). Conclusions: Macronutrient intake adequacy by the investigated lactating women has influenced their WC and AC evolution. This outcome has evidenced the important role played by nutritional monitoring in puerperium to prevent abdominal fat retention after pregnancy.