To read the full abstract: Diabetes Care. 2019 Jun;42(6):10091017. PMID: 30967436
Gestational diabetes mellitus (GDM) is increasing in incidence, affecting approximately 14% of pregnancies. Preventing GDM may significantly improve outcome for both mothers and offspring. The pathogenesis of GDM involves insulin resistance, pancreatic beta-cell failure and an increase in inflammatory markers. Both probiotics and the n-3 long-chain polyunsaturated fatty acids (LC-PUFA) present in fish oil have been demonstrated to possess anti-inflammatory properties and a capability to reduce insulin resistance. Furthermore, a combination of these two active components might exert synergistic immunoregulatory effects.
To test a novel way to prevent GDM, the authors conducted a randomized, placebo-controlled intervention trial of a dietary supplementation. The hypothesis was that fish oil and probiotic supplements, either individually or in combination, could improve blood glucose control during pregnancy and prevent GDM by reducing insulin resistance and inflammation. 439 women at risk for GDM were randomized into four intervention groups: fish oil + placebo, probiotics + placebo, fish oil + probiotics, and placebo + placebo. Although the fish oil and probiotics were well tolerated with no side effects, they found no difference in any maternal and neonatal outcome; primarily the various diets conferred no benefit in lowering the risk of GDM.
This was the first study to use a combination of fish oil and probiotics but found no benefit in lowering the risk of GDM. The findings are consistent with a previous study reporting no benefit of fish oil supplementation (1) but a recent meta-analysis of 7 clinical trials found that supplementation with Omega-3 fatty acids has substantial benefits on glycemic control and inflammatory responses (2). The putative mechanisms by which fish oil and probiotics might improve the outcome in GDM include improvements in intestinal barrier integrity and reduction in the risk of metabolic endotoxemia and subsequent low-grade inflammation. It seems that there is still uncertainty whether probiotics and fish oils impact GDM outcomes and thus further studies are required.
1. Gao L, Lin L, Shan N, et al. The impact of omega-3 fatty acid supplementation on glycemic control in patients with gestational diabetes: a systematic review and meta-analysis of randomized controlled studies. J Matern Fetal Neonatal Med 2018:17.
2. Zhou SJ, Yelland L, McPhee AJ, Quinlivan J, Gibson RA, Makrides M. Fish-oil supplementation in pregnancy does not reduce the risk of gestational diabetes or preeclampsia. Am J Clin Nutr 2012;95:13781384.