Diet and exercise do not reduce the risk of gestational diabetes

The hypothesis that minimizing weight gain in obese pregnant women is helpful in preventing gestational diabetes has not been confirmed. This has been demonstrated by a study conducted by the Division of Endocrinology and Metabolism of MedUni Vienna. Indeed, it may even be detrimental to the mother and the fetus to limit carbohydrate intake during pregnancy. These results were recently published in the journal "Diabetes Care".

Gestational diabetes is a form of diabetes that occurs during pregnancy and, in most cases, disappears again – at least temporarily – immediately after birth. It is badumed that in Austria, as in the rest of Europe, one in seven pregnant women is affected. Unfortunately, no specific data is available because the data of the maternity card (Mutter-Kind-Pbad) collected throughout the country are not yet evaluated centrally. Estimates suggest that about one-third of the affected women are also obese.

One of the main risk factors is obesity in the expectant mother. The pregnancy-weight gain recommended for obese women is 5 to 9 kg, but many women far exceed these recommendations. In order to explore the possibilities and indicators for avoiding gestational diabetes in obese women, nutritional lifestyle interventions involving 436 women were evaluated in the EU DALI project (Vitamin D intervention). and Lifestyle for gestational diabetes), in which the Division Endocrinology and Metabolism, led by endocrinologist Alexandra Kautzky-Willer, played a major role.

The project involved encouraging a group of obese pregnant women to modify their diet and to comply with five measures aimed at reducing their consumption of soft drinks, reducing their consumption of rapidly absorbed carbohydrates and lipids, and increasing their consumption of protein. and dietary fiber. . The control group did not make any changes to their eating habits. A second group of women practiced regular physical activity and received the corresponding advice. The control group did not take any physical exercise.

Although the weight gain of women who followed the dietary advice was lower, they also had higher fasting blood glucose levels and a higher rate of substances in the blood resulting from increased fat degradation, such as fatty acids and ketones. This has also been correlated with reduced carbohydrate intake. Higher levels of free fatty acids have also been found in the blood of newborns. No changes were found in these metabolic markers in the other groups. However, according to the study, an increase in physical activity did not prevent gestational diabetes in the same way as vitamin D supplementation.

In summary, it can be concluded that nutritional interventions have a significant influence on the metabolism of mother and infant. However, the benefit of reduced weight gain by limiting carbohydrates in obese pregnant women simultaneously leads to an increase in fat breakdown and the badociated release of free fatty acids into the blood of the mother and baby. The consequences of this situation are not yet clear and need to be deepened.

Kautzky-Willer says:

Gestational diabetes is the leading risk factor for type II diabetes in women after childbirth and also increases the risk of the child through fetal programming. The development of preventive measures during and after pregnancy is an important goal in the fight against the diabetes epidemic. It may be that low carb diets are not ideal for pregnant women. "

Jürgen Harreiter, endocrinologist and co-author of the study, adds:

Evidence of ideal weight gain during pregnancy is still not definitive, especially in the case of obese women, and require further study. "