Estimation of protein requirements in Indian pregnant women using a whole-body potassium counter

Abstract

Background The 2007 World Health Organization/Food and Agriculture Organization/United Nations University (WHO/FAO/UNU) recommendation for the Estimated Average Requirement (EAR) of additional protein during pregnancy for a gestational weight gain (GWG) of 12 kg (recalculated from a GWG of 13.8 kg) is 6.7 and 21.7 g/d in the second and the third trimester, respectively. This EAR is based on measurements of potassium accretion in high-income country (HIC) pregnant women. It is not known if low- to middle-income country, but well-nourished, pregnant women have comparable requirements. Objective We aimed to estimate total body potassium (TBK) accretion during pregnancy in Indian pregnant women, using a whole-body potassium counter (WBKC), to measure their additional protein EAR. Methods Well-nourished pregnant women (20–40 y, n = 38, middle socioeconomic stratum) were recruited in the first trimester of pregnancy. Anthropometric, dietary, and physical activity measurements, and measurements of TBK using a WBKC, were performed at each trimester and at birth. Results The mid-trimester weight gain was 2.7 kg and 8.0 kg in the second and the third trimester, respectively, for an average 37-wk GWG of 10.7 kg and a mean birth weight of 3.0 kg. Protein accretion was 2.7 and 5.7 g/d, for an EAR of 8.2 and 18.9 g/d in the second and the third trimester, respectively. The additional protein EAR, calculated for a GWG of 12 kg, was 9.1 and 21.2 g/d in the second and the third trimester, respectively. Conclusion The additional protein requirements of well-nourished Indian pregnant women for a GWG of 12 kg in the second and third trimesters were similar to the recalculated 2007 WHO/FAO/UNU requirements for 12 kg.

Protein intakes of pregnant women and children in India—protein quality implications

“…b Maintenance protein requirement of the gestational weight gain over the second and third trimesters, expressed per kilogram body weight per day. Body weight was calculated as sum of end of first trimester body weight and second or third trimester gestational weight gain (Kuriyan et al, 2019). c Additional protein requirement for foetal growth at each trimester, expressed per kilogram body weight per day (body weight was calculated as described above; Kuriyan et al, 2019).…”

“… b Maintenance protein requirement of the gestational weight gain over the second and third trimesters, expressed per kilogram body weight per day. Body weight was calculated as sum of end of first trimester body weight and second or third trimester gestational weight gain (Kuriyan et al, 2019). …”

“…For the second and third trimesters, the additional IAA requirements for tissue deposition were calculated separately using mean values of foetal tissue IAA composition from 12–24 and 28–40 weeks, respectively (Widdowson, 1980). The scoring pattern was calculated as the ratio of the body weight‐corrected IAA requirement (mg·kg −1 ·day −1 ) and the body weight‐corrected total protein requirement (g·kg −1 ·day −1 ) for the pregnant women studied (Kuriyan et al, 2019).…”

“…To compute the additional daily IAA requirement during pregnancy (separately for second and third trimesters), a factorial approach was used, with recent estimations of total body potassium accretion based additional protein requirements in well-nourished, middle socio-economic stratum South Indian pregnant women with a total gestational weight gain (GWG) of 10.7 kg (Kuriyan et al, 2019). In the present analyses, using the factorial approach, the additional IAA requirements were calculated as a sum of IAA requirements for growth (newly deposited tissue) and maintenance of the total GWG (including maintenance of the newly deposited tissue).…”

“…For the second and third trimesters, the additional IAA requirements for tissue deposition were calculated separately using mean values of foetal tissue IAA composition from 12-24 and 28-40 weeks, respectively (Widdowson, 1980). The scoring pattern was calculated as the ratio of the body weight-corrected IAA requirement (mgÁkg −1 Áday −1 ) and the body weight-corrected total protein requirement (gÁkg −1 Áday −1 ) for the pregnant women studied (Kuriyan et al, 2019 (Kashyap et al, 2018;Kashyap et al, 2019) were used to calculate the DIAAS of supplementary food sources, that is, legume, egg, and meat, respectively, for pregnant women. For cereal protein, the true ileal IAA digestibility of rice was used from the study on children <2 years (Shivakumar et al, 2019), whereas the digestibility of cow's milk was assumed to be the same as hen's egg protein from the study on adults (Kashyap et al, 2018).…”