Can a healthy diet prevent gestational diabetes?

The post hoc analysis of St. Carlos Gestational Diabetes Mellitus (GDM) Prevention Study published in Nutrients journal demonstrated the effect of late first trimester (>12 gestational weeks) adherence to a six food target Mediterranean Diet (MedDiet) pattern (>12 servings/week of vegetables, >12 servings/week of fruits, <2 servings/week of juice, >3 servings/week of nuts, >6 days/week consumption of extra virgin olive oil (EVOO) and ≥40 mL/day of EVOO) in 874 women. High adherence (5-6 food targets) to MedDiet was associated with 65% reduced risk of gestational diabetes mellitus (GDM) and 77% lower risk of composite of materno-fetal complications (emergency C-section, perineal trauma, pregnancy-induced hypertension and preeclampsia, prematurity, large for gestational age/small for gestational age) with the odds ratio [0.35 (95% CI 0.18-0.67), p= 0.002] and [0.23 (95% CI 0.11-0.48), p <0.001], respectively1.

Therefore, incorporating a healthy diet during pregnancy is integral to the prevention of GDM.
GDM is the initial onset of glucose intolerance or diabetes during pregnancy2. The prevalence of GDM is high in certain Asian countries, especially in Singapore (27.0%), India (24.9%), Thailand (22.9%), Malaysia (22.1%) and Vietnam (19.8%)3. Increasing prevalence of GDM is alarming particularly in obese South Asian women (BMI >30 kg/m2) who might have a 70% chance of GDM3,4.

Hyperglycemia during pregnancy not only impacts the health of the mother, but also the child.
Lowe et al.5, in their post hoc Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study followed up a cohort of 4697 mothers and 4832 children for a median of 11.4 years postpartum and established that gestational diabetes was associated with an overall 52.2% risk of glucose metabolism disorder (composite of type 2 diabetes or prediabetes) among mothers with GDM and greater adiposity (39.5% overweight or obese) among their children.
GDM not only increases the risk of type 2 diabetes in women and adiposity in their children, it is also associated with an increased incidence of hypertension and cardiovascular diseases in mothers and type 2 diabetes and metabolic syndrome in their children6,7.
Given the risks associated with GDM and their increasing health concerns, its prevention is of utmost importance. Therefore, lifestyle modification with diet and exercise is vital to manage GDM8.

De la Torre and colleagues9 in their prospective interventional study evaluated the effectiveness of early MedDiet nutritional intervention supplemented with EVOO and pistachios in clinical practice. During the follow-up of normoglycemic pregnant women (n= 932), the incidence of GDM was 13.9% (n=130), which was significantly lower than the control (GDM 23.4%) and intervention (GDM 17.1%) groups from their previous St. Carlos GDM prevention study10. 72.8% (n=100) of these women were managed with diet and only 27.2% (n=30) required insulin treatment9. Therefore, St. Carlos GDM studies are pivotal in emphasizing the significance of MedDiet in reducing the burden of GDM.
Besides, Mijatovic-Vukas et al.2 in their systemic review have also highlighted the association of MedDiet, DASH (Dietary Approaches to Stop Hypertension) diet and AHEI (Alternate Healthy Eating Index) diet to 15-38% decreased relative risk of GDM. Furthermore, they reviewed that any pre-pregnancy physical activity and early pregnancy physical activity had 30% and 21% reduced risk of GDM, respectively.

In conclusion, GDM is a highly preventable condition, which can be controlled by following a healthy lifestyle by incorporating dietary changes (MedDiet/DASH diet) and increasing physical activity before or early in pregnancy.


1. Assaf-Balut C, García de la Torre N, Fuentes M, Durán A, Bordiú E, Del Valle L, Valerio J, Jiménez I, Herraiz MA, Izquierdo N, Torrejón MJ, de Miguel MP, Barabash A, Cuesta M, Rubio MA, Calle-Pascual AL. A High Adherence to Six Food Targets of the Mediterranean Diet in the Late First Trimester is Associated with a Reduction in the Risk of Materno-Foetal Outcomes: The St. Carlos Gestational Diabetes Mellitus Prevention Study. Nutrients. 2018;11(1):66.
2. Mijatovic-Vukas J, Capling L, Cheng S, Stamatakis E, Louie J, Cheung NW, Markovic T, Ross G, Senior A, Brand-Miller JC, Flood VM. Associations of Diet and Physical Activity with Risk for Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis. Nutrients. 2018;10(6):698.
3. Guariguata L, Linnenkamp U, Beagley J, Whiting DR, Cho NH. Global estimates of the prevalence of hyperglycemia in pregnancy. Diabetes Research and Clinical Practice. 2014;103(2):176–185.
4. Wong VW, Lin A, Russell H. Adopting the new World Health Organization diagnostic criteria for gestational diabetes: How the prevalence changes in a high-risk region in Australia. Diabetes Research and Clinical Practice. 2017;129:148–153.
5. Lowe WL Jr, Scholtens DM, Lowe LP, Kuang A, Nodzenski M, Talbot O, Catalano PM, Linder B, Brickman WJ, Clayton P, Deerochanawong C, Hamilton J, Josefson JL, Lashley M, Lawrence JM, Lebenthal Y, Ma R, Maresh M, McCance D, Tam WH, Sacks DA, Dyer AR, Metzger BE; HAPO Follow-up Study Cooperative Research Group. Association of Gestational Diabetes With Maternal Disorders of Glucose Metabolism and Childhood Adiposity. JAMA. 2018;320(10):1005-1016.
6. Daly B, Toulis KA, Thomas N, Gokhale K, Martin J, Webber J, Keerthy D, Jolly K, Saravanan P, Nirantharakumar K. Increased risk of ischemic heart disease, hypertension, and type 2 diabetes in women with previous gestational diabetes mellitus, a target group in general practice for preventive interventions: A population-based cohort study. PLoS Medicine. 2018;15(1):e1002488.
7. Grunnet LG, Hansen S, Hjort L, Madsen CM, Kampmann FB, Thuesen ACB, Granstrømi C, Strøm M, Maslova E, Frikke-Schmidt R, Damm P, Chavarro JE, Hu FB, Olsen SF, Vaag A. Adiposity, Dysmetabolic Traits, and Earlier Onset of Female Puberty in Adolescent Offspring of Women With Gestational Diabetes Mellitus: A Clinical Study Within the Danish National Birth Cohort. Diabetes Care. 2017;40(12):1746-1755.
8. Brown J, Alwan NA, West J, Brown S, McKinlay CJ, Farrar D, Crowther CA. Lifestyle interventions for the treatment of women with gestational diabetes. Cochrane Database Systemic Review. 2017;5(5):CD011970.
9. de la Torre NG, Assaf-Balut C, Jiménez Varas I, Del Valle L, Durán A, Fuentes M, Del Prado N, Bordiú E, Valerio JJ, Herraiz MA, Izquierdo N, Torrejón MJ, Cuadrado MA, de Miguel P, Familiar C, Runkle I, Barabash A, Rubio MA, Calle-Pascual AL. Effectiveness of Following Mediterranean Diet Recommendations in the Real World in the Incidence of Gestational Diabetes Mellitus (GDM) and Adverse Maternal-Foetal Outcomes: A Prospective, Universal, Interventional Study with a Single Group. The St Carlos Study. Nutrients. 2019;11(6):1210.
10. Assaf-Balut C, García de la Torre N, Durán A, Fuentes M, Bordiú E, Del Valle L, Familiar C, Ortolá A, Jiménez I, Herraiz MA, Izquierdo N, Perez N, Torrejon MJ, Ortega MI, Illana FJ, Runkle I, de Miguel MP, Montañez C, Barabash A, Cuesta M, Rubio MA, Calle-Pascual AL. A Mediterranean diet with additional extra virgin olive oil and pistachios reduces the incidence of gestational diabetes mellitus (GDM): A randomized controlled trial: The St. Carlos GDM prevention study. PLoS One. 2017;12(10):e0185873.