Consumption of Vitamin B during pregnancy does not increase the risk of allergy in the infants, says a new study from Japan that challenges previous findings. Maternal consumption of folate and vitamins B2, B6, and B12 during pregnancy was not associated with the risk of the infant developing asthma or eczema, according to findings from 763 infants published in Pediatric Allergy and Immunology.
The link between folate and folic acid, the synthetic form of the vitamin, and respiratory health is not clear cut, with contradictory results reported in the literature. A study from Johns Hopkins Children’s Center found that higher levels of folate were associated with a 16 per cent reduction of asthma in (Journal of Allergy & Clinical Immunology, June 2009, Vol. 123, pp. 1253-1259.e2). However, a Norwegian study reported that folic acid supplements during the first trimester were associated with a 6 per cent increase in wheezing, a 9 per cent increase in infections of the lower respiratory tract, and a 24 per cent increase in hospitalisations for such infections, (Archives of Diseases in Childhood, doi:10.1136/adc.2008.142448). In addition, researchers from the University of Adelaide in Australia reported that folic acid supplements in late pregnancy may increase the risk of asthma by about 25 per cent in children aged between 3 and 5 years (American Journal of Epidemiology, 2010, doi:10.1093/aje/kwp315).
Illumination from the Land of the Rising Sun?
The new study, performed by researchers from Fukuoka University, the University of Tokyo, and Osaka City University, goes beyond folate and folic acid, and reports no link between Vitamin B intake and the risk of asthma or eczema in children. “To the best of our knowledge, there has been no birth cohort study on the relationship between maternal consumption of Vitamin B during pregnancy and the risk of allergic disorders in the offspring,” wrote the researchers. The findings were based on data from 763 pairs of Japanese mother and child. A diet history questionnaire was used to assess maternal intakes of the various B vitamins during pregnancy, and the infants were followed until the age of 16 to 24 months. Japan has no mandatory fortification of flour with folic acid.
Results showed that, according to criteria from the International Study of Asthma and Allergies in Childhood, 22 and 19 percent of the children had symptoms of wheeze and eczema, respectively, but there was no association between these children and the dietary intakes of the various B vitamins by their mothers. “Our results suggest that maternal intake of folate, vitamin B12, vitamin B6, and vitamin B2 during pregnancy was not measurably associated with the risk of wheeze or eczema in the offspring,” said the researchers. “Further investigation is warranted to draw conclusions as to the question of whether maternal Vitamin B intake during pregnancy is related to the risk of childhood allergic,” they concluded.
According to the European Federation of Allergy and Airway Diseases Patients Association (EFA), over 30m Europeans suffer from asthma, costing Europe €17.7bn every year. The cost due to lost productivity is estimated to be around €9.8bn. The condition is on the rise in the Western world and the most common long-term condition in the UK today. According to the American Lung Association, almost 20m Americans suffer from asthma. The condition is reported to be responsible for over 14m lost school days in children, while the annual economic cost of asthma is said to be over $16.1bn.
Source: Pediatric Allergy and Immunology. Volume 22, Issue 1-Part-I, February 2011, Pages: 69–74 DOI: 10.1111/j.1399-3038.2010.01081.x
“Maternal B vitamin intake during pregnancy and wheeze and eczema in Japanese infants aged 16–24 months: The Osaka Maternal and Child Health Study”. Authors: Y. Miyake, S. Sasaki, K. Tanaka, Y. Hirota
A lack of testing for food allergies is putting children's health at risk and could lead to life threatening reactions, a study has found. The study, Adverse reactions to food in New Zealand children age 0-5 years, was published in the New Zealand Medical Journal. It looked at a cross-section of 110 children who had attended Plunket clinics. It found 44 had experienced an adverse reaction to food, but only four had been clinically evaluated. Those children were found to have adverse reactions to food allergens, including a life threatening peanut allergy. Two others had been hospitalised with systemic symptoms, but neither had undergone testing for food allergy. “If these children have food allergies, they remain at risk for continued and possibly severe reactions,” the study said.
Parents modifying children's diets or breastfeeding mothers cutting out food without advice from a physician or dietician could also have adverse affects, it said. “Failure to thrive is commonly seen in children experiencing FA (food allergy) as a result of multiple foods being removed from their diet.” The data indicated adverse reactions to food were a public health concern and may be under investigated — even when symptoms were severe, the study said.
“There is an urgent need to investigate the epidemiology, diagnosis, and prevention of FA (food allergy) in New Zealand to reduce morbidity, improve child health, and reduce the burden to health costs.” Thirty-three of the children were reported to have eczema. Ten had worsening symptoms two hours after eating, the study said. Symptoms improved in six of them with dietary changes. Doctors had prescribed topical therapy for 18 of those children with eczema, but symptoms had persisted.
“One possible explanation for this observation is undiagnosed FA (food allergy). Without testing, allergic triggers for eczema could not be identified in these participants.” Further investigation of food allergy as the cause of eczema was warranted, the study said.
Adverse reactions to food worldwide in children was an increasing concern and food allergy was as common in New Zealand as in other countries, the study said. The study was conducted by the Auckland District Health Board and led by Associate Professor Rohan Ameratunga and lead researcher Dr Christine Crooks. Allergy New Zealand chief executive Penny Jorgensen said the study was “really disturbing” because it highlighted that many children were not being assessed for food allergy. The risk was the potential for life-threatening reactions, she said.
A new study shows that adolescents who take acetaminophen, better known as Tylenol, have a higher risk of asthma, allergic nasal conditions and the skin disorder eczema.
Acetaminophen is widely viewed as a very safe drug—one reason why hospitals use it routinely as a painkiller instead of aspirin or ibuprofen. The major problem associated with it is liver damage caused by overdoses. Recently, however, there has been a growing drumbeat about possible dangers from the drug. One study, for example, found that acetaminophen increased the risk of hearing loss in men. And some others have hinted that the drug is linked to asthma in newborns whose mothers used the drug during pregnancy and in young children exposed to it.
The new findings were reported in the American Journal of Respiratory and Critical Care Medicine by researchers in the International Study of Asthma and Allergies in Childhood. The team, headed by epidemiologist Richard Beasley of the Medical Research Institute in Wellington, New Zealand, gave written questionnaires to 322,959 13- and 14-year-olds in 50 countries exploring their use of acetaminophen, other drugs, and asthma symptoms. They were also shown a video containing five scenes of clinical asthma and asked whether they had experienced any symptoms similar to those shown. About 73% of the teens said they had used acetaminophen at least once in the previous year and 30% said they had used it monthly.
Taking into account maternal education, smoking, diet and siblings, the team found that those subjects who had used the drug at least once per year were 43% more likely to have asthma, while those who used it at least monthly were 2.5 times as likely to suffer from the condition. The risk of rhinoconjunctivitis (a severe nasal congestion) was 38% higher for those who used it once per year and 2.39 times as high for those who used it at least monthly. The comparable increases in risk for eczema were 31% and 99%, respectively.
Overall, the increased risk of asthma associated with acetaminophen was 41%, the authors found. That could, at least in part, explain why there has been an increase in the prevalence of asthma in the 50 years since the drug was introduced. Given the widespread use of the drug, it could also represent a large public health problem.
But—and it is a very big but—the study shows only an association, not causality. That could only be determined by a randomized clinical trial, which the authors recommend. Furthermore, the study relies on the recall of teenagers. Recall is notoriously inaccurate in adults, and it is probably worse in adolescents, clouding the results. For the time being then, you can probably continue to feel comfortable giving the drug to your children.
In a statement, McNeil Consumer Healthcare, which manufactures Tylenol, said that the drug “has over 50 years of clinical history to support its safety and effectiveness” and that no clinical trial has demonstrated that the drug causes asthma.