Vitamin D deficiency in pregnant women

Women in pregnancy often have vitamin D deficiency

05/25/2013

In Germany, pregnant women and their unborn children are usually not sufficiently supplied with vitamin D. A British study shows that it is not only in winter to deficits.

Sunlight essential for vitamin D supply
A renewed period of bad weather such as Germany is currently experiencing also reduces the possibility of supplying itself with sufficient vitamin D („“), because sunlight is essentially responsible. However, the weather is not the only reason why many pregnant women and their unborn children in Germany are insufficiently supplied with vitamin D. This is documented in a cross-sectional study in „British Journal of Nutrition“ (2013; doi: 10.1017 / S0007114513001438) deficits not only in the winter months. In the case of many mothers and their children, there is a shortage even in summer. Sunlight is also important here because most foods consumed in Germany contain too little vitamin D. Especially the vitamin can be found in cod liver oil, salmon, eel, sardines, chicken eggs and mushrooms. („“) Vitamin D, the sun hormone, is not only absorbed through food, but is also formed on our skin by solar radiation. However, their intensity in Germany in the months from October to March is usually too low for sufficient formation of vitamin D..

Lack of physical exercise as a risk factor
In the winter months, the 25 (OH) vitamin D levels (to determine the body's vitamin D content) were below 50 nmol / l in 98 percent of pregnant women, which is considered the threshold for adequate care. However, even in the summer months, 49 percent of them were underserved. The children are affected as well. The team headed by Clemens Kunz from the Institute of Nutrition Science of the University of Gießen also determined the concentration in the umbilical cord blood and came to the conclusion that in the winter months, 94 percent of the children and in the summer months 35 percent were underserved. The most important risk factors for a vitamin deficit were identified as lack of physical activity and origin from a non-European country. Sport may be a marker for staying outdoors and a dark skin color for the decreased vitamin synthesis in the skin. For mother and child in particular, adequate vitamin D supplementation is important, as a deficiency increases Kunz's risk of pregnancy complications such as gestational diabetes, gestosis and preterm labor. In addition, vitamin D deficiency can lead to disorders of bone formation, lung diseases and diabetes mellitus in the newborn.

Too high vitamin D intake during pregnancy is not a problem?
In Germany, infants have long been substituted with vitamin D in the context of rickets prophylaxis. According to the study, Kunz believes that pregnant women should take vitamin D. Since leaflets on vitamin D tablets are often used to warn against over-delivery during pregnancy, women often leave their fingers off. According to the expert, this is a misinformation. The substituted vitamin D, whether in tablet form or via the UV light in the skin, is initially inactive and thus hardly to be feared an overdose. Only in the kidney is the active form produced. Prof. Kunz explained that, however, the synthesis is based on demand and that too much ingested vitamin D is broken down in the body and excreted again. However, there are also opinions that suggest that dangerous overdoses may occur, such as that acute or chronic vitamin D overdose may result in vitamin D hypervitaminosis. Or that in infants with a small genetic defect due to vitamin D prophylaxis, a life-threatening increase in the concentration of calcium in the blood can occur. In an observational study, it is now planned to test in pregnant women whether, following a doctor-diagnosed vitamin D deficiency, the intake of 1,000 IU (International Units) of vitamin D daily during the entire pregnancy is sufficient to ensure the desired care. (Sb)

Picture: JMG