Oral Presentation Women's Health Forum 2021

Dietary fibre consumption in overweight and obese women has minimal influence on gut microbiota composition in late pregnancy (#22)

Chelsea L Vanderpeet 1 , Helen L Barrett 2 , Leonie K Callaway 3 , David H McIntyre 4 , James S.M Cuffe 1 , Marloes Dekker Nitert 2
  1. School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
  2. School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
  3. Women's and Newborns, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
  4. Mater Medical Research Institute , The University of Queensland, Brisbane, Queensland, Australia

            Dietary fibre is known to have beneficial effects on gut microbiota community structure and behaviour. Fibre supports the growth of ‘health-promoting’ bacteria that ferment this dietary component to produce short-chain fatty acids (SCFA). SCFA are absorbed into circulation, where they promote host health through regulation of metabolic pathways. Whether this relationship persists in the context of pregnancy is unclear. Therefore, this study investigated whether varied dietary fibre intake translated to differences in gut microbiota composition and serum SCFA concentrations in late pregnancy.

            Gut microbiota profiles were examined using 16s rRNA gene amplicon sequencing in 27 low-fibre and 25 adequate-fibre consuming women from the SPRING (Study of PRobiotics IN Gestational diabetes) cohort at 28 weeks gestation. Very few women had fibre intake above recommended levels and these were included in the adequate-fibre group. Energy-adjusted dietary intake was correlated with genera abundance and gut microbiota composition compared between groups. Circulating SCFAs in serum were analysed by LC-MS. Dietary intake (mg/kJ) correlated with the abundance of a number of genera, but dietary fibre consumption had minimal effects on gut microbiota composition. Low-fibre intake was linked to a greater abundance of Sutterella and Bacteroides, with no major associations with greater fibre intake and the presence of ‘health-promoting’, SCFA-producing bacteria. Serum Acetate, Propionate, and Butyrate were similar between groups.

            While adequate-fibre consumption was linked to reduced abundance of Sutterella and Bacteroides, it was not associated with greater numbers of SCFA-producing bacteria typically associated with dietary fibre consumption. Coupled with the similar serum SCFA levels between groups, this suggests that the differences in low- and adequate-fibre consumption are not enough to promote the expansion of SCFA-producing bacteria in overweight and obese pregnant women at 28-weeks gestation. Additional studies are required to establish if high fibre intake can promote this expansion in late pregnancy.