Poster Topical Area: Maternal, Perinatal and Pediatric Nutrition
Location: Hall D
Poster Board Number: 348
Objective: To assess the magnitude of the association between human milk fat content (MF) with percent body fat (%BF) estimated by bioelectrical impedance analysis (BIA) as compared to %BF from predictive equations calculated with body mass index (BMI) in urban lactating women in the Western Highlands of Guatemala.
Methods: 40 lactating women with infants aged between 37-194 days from the urban area of Quetzaltenango, Guatemala, were recruited to this study by convenience sampling. Participation was voluntary with written consent. At least 30 mL breastmilk from each participant was collected using manual milk pumps by trained researchers. Weight, height and waist circumference were measured by trained anthropometrists. BIA was conducted with the Medical Body Composition Analyzer SECA®525. MF (g/L) was measured by creamatocrit using Lucas's equation (1978). %BF was determined using the two equations from BMI (kg/m²) as well as direct reading from BIA. Separately, linear association was tested between the %BF values from three estimations with MF.
Results: The participants had an average age of 24.9 years old (range: 17-37 y). The mean of waist circumference was 86.5 cm (range: 69-110). The participants had a BMI mean of 25.0 kg/m2 (range: 19.4-35.9). There were 13 overweight women (25≤BMI<30), 4 obese (BMI≥30), and none was underweight (BMI<18.5). The means of %BF from BMI calculation were 30.4% (SD±4.9) and 31.9% (SD±4.9) (Deurenberg & Gallagher, respectively), and that from BIA was 35.3% (SD±6.7). The mean MF was 31.5 g/L (SD±16.7). The %BF values from Deurenberg and Gallager equations were linearly associated with MF, respectively expressed as MF (g/L) = 0.105*%BF (R = 0.91, p<0.0001) and MF (g/L) = 0.100*%BF (R = 0.91, p<0.0001). This linear association was also found between the %BF from BIA and MF: MF (g/L) = 0.089*%BF (R = 0.90, p<0.0001).
Conclusion: Although participation from a wider range of lactation stage is recommended for future studies, %BF generated from BMI equations and BIA could all be good predictors of human milk fat content between 37 and 194 postpartum days in Guatemalan mothers, confirming prior findings. This vouches for appropriate full-breast extraction and sample homogenization as well as relative validity of all %BF approaches.
Tufts University School of Medicine