ISLAMABAD – High vitamin D levels in expectant mothers appear to raise the risk of children developing a food allergy after birth, a new study has found.
The survey carried out by the Helmholtz Centre for Environmental Research and the Martin Luther University in Halle-Wittenberg in Germany has concluded that pregnant women should avoid taking vitamin D supplements.
Dr Kristin Weibe`s team from Leipzig used samples from the LiNA cohort that the Helmholtz Centre for Environmental Research (UFZ) had established together with the St. Georg municipal clinic between 2006 and 2008 headed by Dr. Irina Lehmann.
The level of vitamin D was tested in the blood of the pregnant mothers and also in the cord blood of the children born. In addition to this, questionnaires were used to assess the occurrence of food allergies during the first two years of the children`s lives.
The result was clear: in cases where expectant mothers were found to have a low vitamin D level in the blood, the occurrence of food allergies among their two-year old children was rarer than in cases where expectant mothers had a high vitamin D blood level.
In reverse, this means that a high vitamin D level in pregnant women is associated with a higher risk of their children to develop a food allergy during infancy.
Furthermore, those children were found to have a high level of the specific immunoglobulin E to food allergens such as egg white, milk protein, wheat flour, peanuts or soya beans.
The UFZ scientists also got evidence for the mechanism that could link vitamin D and food allergies.
Dr Gunda Herberth - also from the Department of Environmental Immunology at the UFZ - took a closer look at the immune response of the affected children and analysed regulatory T-cells in cord blood in particular. The cells are capable of preventing the immune system from overreacting to allergens, with the result that they protect against allergies.
The UFZ researchers know from earlier analyses that the allergy risk increases in cases where too few regulatory T-cells are present in cord blood. The interesting result of the current research project: the higher the level of vitamin D found in the blood of mothers and children, the fewer regulatory T-cells could be detected. The correlation could mean that vitamin D suppresses the development of regulatory T-cells and thus increases the risk of allergy.
Apart from diet, Dr. Kristin Weibe explained that the level of vitamin D is mainly affected by conditions such as season, exposure to the sun and the amount of time spent outdoors - these factors were also taken into account in the current risk analyses of vitamin D and food allergy.
Even though the occurrence of food allergies is undoubtedly affected by many other factors than just the vitamin D level, it is still important to take this aspect into consideration.
Hypertension during pregnancy may affect kids` health
Mild maternal hypertension early in pregnancy actually benefits the fetus, but that late-pregnancy hypertension has negative health consequences for the child, a new study has found. The study, conducted by researchers from the Centre for Social Evolution at the Department of Biology, University of Copenhagen, is based on more than 750,000 births in Denmark, with follow-up data on children`s hospital diagnoses for up to 27 years.
“It has been known for some time now that pregnancy-induced hypertension can lead to more serious toxic conditions ( preeclampsia ), but it has puzzled biologists why such a medical condition that can be quite dangerous for both mother and child has not previously been removed by natural selection in our stoneage ancestors,” said Professor Jacobus Boomsma, Director of the Centre for Social Evolution and coordinator of the study.
“However, evolutionary theory also emphasizes that paradoxes of this kind can be due to genetic parent-offspring conflicts, so we set out to test whether we could find statistical evidence for that type of explanation,” he stated.
The results clearly indicate that mothers with minor increases in blood pressure in the first trimester of pregnancy have babies that enjoy generally better health than children of mothers who never get a hypertension diagnosis during pregnancy.
The difference was between 10 and 40 percent fewer diagnoses across all disease categories during the 27 years of available follow-up data, a result that has never been documented before.
However, when hypertension continues or starts later in pregnancy, this advantage shifts to a ca. 10 percent disadvantage in terms of an increased risk of acquiring a diagnosis in the Danish public health data bases.
Child mortality during the first year of life showed the same trend. In spite of this risk being very low in Denmark, no children of mothers with early pregnancy-induced hypertension died, whereas the mortality risk of children born to mothers with hypertension late in pregnancy was above average.
Parent-offspring-conflict theory maintains that father-genes in the placenta will have a tendency to `demand` a somewhat higher level of nutrition for the fetus than serves the interests of mother-genes. It argues that father genes that somehow manage to enhance maternal blood pressure will likely be met by maternal genes compensating this challenge.
Both types of genes are 50/50 represented and thus likely to find a `negotiated` balance while creating an optimally functioning placenta. However, when the pull of paternal genes cannot quite be managed by maternal counterbalances, there is a risk of elevated blood pressure to develop and persist, leading to late occurring pregnancy complications and compromised offspring health.
The results obtained are consistent with the idea that some deep fundamental conflicts lay buried in our genes right from the moment of conception. Imprinted genes are prime suspects for mediating such conflicts as they `remember` which parent they come from.
“Molecular biologists have recently found many such genes in mice and man, and they are particularly expressed in the placenta as the theory predicts. Our study therefore suggests that further research to test whether different patterns of pregnancy-induced hypertension are indeed related to paternal or maternal imprints would be highly worthwhile,” said PhD student Birgitte Hollegaard, who did the analyses together with EU Marie Curie Postdoctoral Fellow Sean Byars.
The authors of the study hope these results will help build bridges between their evolutionary inspired public health analyses and established clinical praxis.
“Ultimately we are not only interested in the fundamental science aspects of genome level reproductive conflicts, but also in seeing some of these findings being made more directly useful, for example by adjusting pregnancy monitoring schemes to take long term risks for offspring health into account,” Jacobus Boomsma concluded.
Missed meals in childhood linked to pain, depression in adulthood
Children who missed meals can not only have problem concentrating in school, they may also have a higher risk of experiencing pain and depression in adulthood, a new University of Nebraska-Lincoln study has suggested.
Depression and chronic pain are experienced by 44 percent of working-aged adults and the study shows a correlation between childhood conditions and pain and depression in adulthood.
The study by UNL sociologist Bridget Goosby examines how childhood socio-economic disadvantages and maternal depression increase the risk of major depression and chronic pain in working-aged adults.
Goosby examined a survey of 4,339 adults from the National Comorbidity Survey Replication looking for a relationship between circumstances in childhood and physical and mental health in working-age adults. She specifically looked at data from adults 25 to 64 years old.
Goosby said she was surprised to find that experiencing hunger in childhood can lead to chronic pain and depression in adulthood.
“The most robust child socio-economic condition was experiencing hunger. Kids who missed meals have a much higher risk of experiencing pain and depression in adulthood,” Goosby said.
The study also found that maternal depression had a correlation with adults having depression later in life.
In the study, Goosby noted that those who grew up with parents with less than 12 years of education had a much higher risk of experiencing chronic pain compared to adults with more highly educated parents, a disparity that becomes evident after age 42 and grew larger over time.
With this information, Goosby said she hopes policymakers will pay attention to creating more healthy family dynamics in society and that the study`s results will give policymakers a reason to examine circumstances in early childhood more closely.