ABSTRACT
PURPOSE: To investigate the energy intake (EI), energy expenditure (EE), and body weight changes of solely breastfeeding women during the first six months postpartum. MATERIALS AND METHODS: This is a prospective observational study of lactating women (n = 64). Three-day dietary records were filled in to assess EI. EE was calculated with a short physical activity questionnaire. Energy cost of milk production was not included in EE estimation. RESULTS: Daily EI and EE for the six-month period was 2,000 Kcal and 1,870 Kcal, respectively. Women had a positive energy balance throughout the study period. Nevertheless, they had a significant weight loss of 0.7 kg/month by the first trimester of lactation, but a non-significant weight loss of 0.5 kg/month by the second trimester. Overall, women lost 86% of the weight gained during pregnancy. CONCLUSION: Exclusively breastfeeding women manage to lose weight during the first six months postpartum as part of the natural process of energy cost of lactation.