Breastfeeding history and the risk of overweight and obesity in middle-aged women.

Background: The increased metabolic activity required to sustain breastfeeding and its associated milk production helps to reduce maternal fat stores accumulated during pregnancy. This study aims to assess the association between breastfeeding duration and fatness indices in middle-aged women.

Methods: The analysis was carried out in a group of 7500 parous 55.5 ± 5.3 year old women included body mass index, body fat percentage, and waist-to-height ratio. The likelihood of excessive weight or obesity in relation to total breastfeeding time using multivariate logistic regression analyses.

Results: An analysis of adjusted odds ratios did not show significant associations between breastfeeding duration and the risk of excessive weight and obesity in premenopausal women. After menopause, women who gave birth to 2 children and breastfed 1-6 and > 12 months had a lower risk of abdominal obesity (OR 0.70; 95% CI 0.50-0.99; p = 0.042; and OR 0.68; 95% CI 0.47-0.98; p = 0.039). Women who gave birth to 3 or more children and breastfed for 1-6 months, also showed a lower risk of overweight (OR 0.52; 95% CI 0.27-0.99; p = 0.047), compared to those ones that have never breastfed. There was no relationship found between the duration of lactation and the risk of excessive body fat.

Conclusion: Breastfeeding may have some beneficial, long-term effect on the risk of excessive weight and abdominal obesity in women.