Research highlights potential of nutritional therapy to effectively manage gestational diabetes

New research published in journal nutrients Investigating the role of medically directed nutritional patterns and supplements in the management of gestational diabetes mellitus (GDM).

study: Gestational Diabetes: What Can Medical Nutritional Therapy Do? Image credit: BaLL LunLa / Shutterstock.com

About GDM

GDM affects 1–30% of pregnant women, but its prevalence varies widely by region. GDM is usually diagnosed by an abnormal oral glucose tolerance test (OGTT) between her 24 and 28 weeks. GDM corresponds to fasting, 1-hour, and 2-hour blood glucose levels greater than 92 mg/dL, 180 mg/dL, and 153 mg/dL, respectively.

GDM is often caused by beta cell dysfunction. Beta cells are cells in the pancreas that are no longer able to secrete additional insulin to meet the demands of pregnancy, causing elevated blood sugar levels.

Insulin resistance (IR) is common during pregnancy due to the need for a steady supply of glucose as an energy source for the developing fetus. Towards the end of pregnancy, the IR becomes almost as high as the levels observed in patients with type 2 diabetes mellitus (T2DM). Nevertheless, after delivery, the mother’s insulin sensitivity may return to normal or ultimately continue to be impaired by her T2DM.

The effects of GDM affect both mother and fetus and can cause macrosomia, stillbirth, and metabolic abnormalities in the newborn. For mothers, the long-term risk of diabetes and cardiovascular disease (CVD) is increased. Furthermore, GDM contributes to over 87% of fetal hyperglycemia cases and over 16% of neonatal GDM cases.

What is medical nutritional therapy?

Medical nutritional therapy (MNT) refers to nutritional management to regulate the metabolic state of the body. MNTs often contain foods and nutrients that are effective in managing a variety of chronic medical conditions. This treatment is also relatively inexpensive and is preferred over drug therapy for treatment in GDM.

MNT in GDM maintains healthy blood sugar levels, improves insulin sensitivity, and reduces the risk of multiple adverse pregnancy outcomes. Additionally, MNT protects the fetus from oxidative stress, prevents macrosomia, and reduces the risk of maternal hypertension after delivery.

energy intake

In the absence of international guidelines for energy intake in GDM, general recommendations apply to these patients. These include a total intake of 1,800 kcal per day, which can be increased in the second and third trimesters as necessary to maintain normal weight gain and metabolic parameters.

According to the International Federation of Gynecology and Obstetrics (FIGO), total caloric intake is 30-35 kcal/kg per day. Severe caloric restriction of less than 1,500 kcal per day is not recommended as it may induce ketosis and adversely affect fetal growth and development.

carbohydrate intake

Carbohydrate intake should contribute 35-55% of total energy intake, depending on geography. For example, Chinese patients have a higher proportion of carbohydrates in their recommended diets.

Glycemic index (GI) is the key to determining blood sugar levels after meals. Low GI diets are correlated with improved glycemic control, reduced weight gain during pregnancy, and improved insulin sensitivity. The safety of low GI foods has also been reported. However, further research is needed to confirm its effectiveness as an intervention in GDM.

protein intake

Proteins regulate energy homeostasis, provide satiety, and are essential for both growth and development. A high-protein diet can impair insulin sensitivity and increase the risk of GDM. Plant protein may be preferable to animal protein to reduce GDM risk.

fat intake

Fatty acids are essential for regulating glucose metabolism. Excess fat in the bloodstream can induce insulin resistance by suppressing the uptake of blood sugar into peripheral tissues in response to insulin.

Under normal conditions, fat should account for 30-40% of your total energy. Because carbohydrate intake is restricted in GDM, fat intake is often increased, as reported in previous studies reporting higher triglyceride levels in women with GDM, and these patients You may be more likely to become obese. Nevertheless, replacing carbohydrates with vegetable fats may reduce the risk of GDM.

Insulin sensitivity can be improved by n-3 long chain polyunsaturated fatty acids (LCPUFA) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Both of these are found in the microscopic marine fauna krill. These fats may also attenuate GDM-related changes in fetal neurodevelopment.

vitamins and minerals

Folic acid and vitamin B12 are essential coenzymes for multiple metabolic reactions. Their deficiency is associated with certain types of anemia, DNA damage, and abnormalities in neurodevelopment.

During pregnancy, folic acid and vitamin B12 should be supplemented at the same time to avoid the negative effects of folic acid accumulation. High folate intake without adequate vitamin B12 may increase the risk of GDM. However, the underlying mechanism remains unclear.

Vitamin D deficiency is common at all stages of life. Nevertheless, it is extremely important for successful pregnancy and fetal bone and brain development. Vitamin D supplementation has also been shown to reduce the risk of GDM, which may be due to vitamin D’s role in glucose homeostasis and insulin secretion.

Iodine plays an essential role in a healthy pregnancy as it is central to thyroid hormone production. Excess or insufficient iodine levels can impair thyroid function and increase the risk of GDM.

conclusion

Any dietary program, when used in conjunction with exercise, will successfully treat GDM. Despite previous reports on how GDM can be managed through various diets, guidelines regarding specific foods that can be used to manage this pregnancy complication are still lacking.

Future studies are therefore needed to develop individualized protocols to manage GDM and investigate the potential utility of novel foods like krill that may support this goal.