A Prospective Study of In-utero Exposure to Magnetic Fields and the Risk of Childhood Obesity

OBESITY: excess body fat that adversely effects health; it is a leading cause ofpreventable death in the world and its prevalence is increasing. OVERWEIGHT: having more body fat than is optimally healthy. More people are overweight than obese; obesity is worse than being overweight. This study only looked at obesity rates. 1) This is a prospective study examining whether in-utero exposure to magneticfields (MFs) increases the risk of childhood obesity. 733 pregnant women carried ameter measuring MF levels during pregnancy and their children were followed up to 13 years to collect clinically recorded information on growth patterns and weight. This is the first prospective study to look at this association. 2) The prevalence of childhood obesity is increasing rapidly and has reachedepidemic proportions in both industrialized and newly industrialized countries. 3) It is estimated that this increase in childhood obesity will increase medicalcost by up to $66 billion per year in the U.S. alone. 4) About 20% of US children are obese. [significantly more are overweight] 5) The World Health Organization considers increased obesity the top publichealth challenge. 6) While the efforts to reduce obesity have focused on changing diets andincreasing physical activity with limited success, the causes of the obesity epidemicduring the last several decades remain unclear. 7) Diet and sedentary life style cannot totally explain such a steep world-wideincrease in obesity across countries with vastly differing dietary patterns anddegrees of physical activity. Otherenvironmental factors should be seriouslyexamined, especially in pregnancy, that may damage the formation anddevelopment of fetal endocrine and metabolic systems, predisposing offspring to ahigher risk of developing childhood obesity or becoming overweight. 8) A potential invisible physical risk factor influencing life-long health duringpregnancy is exposure to man-made electromagnetic fields (EMFs) from microwaveovens to countless wireless devices. This parallel in the epidemic ofobesity/overweight with massively increased use of EMF-generating appliances, andwireless networks and devices during the last a few decades warrants closer examination. 9) EMFs exposures during pregnancy have been linked to: * asthma (5 references) * diabetes / overweight/ insulin resistance (2 references) * altered glucose metabolism (2 references) * ADHD (1 reference) * adverse offspring neurological development (1reference) 10) Exposure to EMFs during pregnancy could potentially impact the fetaldevelopment including fetal endocrine and metabolic systems, predisposingoffspring to a higher risk of obesity. 11) EMFs consists of both electric and magnetic fields, but the authors measuredonly magnetic fields. 12) Maternal MF exposure was measured objectively by a MF meter worn byparticipants during pregnancy. 13) The authors controlled for child gender, maternal age, maternal pre-pregnancy BMI, race/ethnicity, education level, smoking during pregnancy, andbreastfeeding, maternal parity, preexisting or gestational diabetes, family income,preterm delivery, and childhood behaviors such as fruit and vegetable intake, TVwatching time, and amount of exercise. 14) In-utero exposure to medium/high MF level was associated with 69%increased risk of being obese or overweight during childhood. 15) There was a dose-response relationship with increasing in-utero MF levelbeing associated with increased risk of obesity/overweight, which was highlystatistically significant. 16) In this prospective cohort study, we present a new finding that a high in-utero MF exposure level in pregnancy is associated with an increased risk ofchildhood obesity. 3 17) The observed association and supporting evidence provide the firstepidemiological link between ever increasing exposure to environmental MFs(especially in-utero exposure) in the last few decades and the rapid rise inchildhood obesity during the corresponding decades. Given the world-wide epidemicof childhood obesity/overweight as a leading public health challenge, our findingshave the potential to reveal a new environmental risk factor for childhood obesity,which may lead to prevention of childhood obesity. 18) The authors hypothesize that the association between MF exposure andchildhood obesity, is linked to altered glucose metabolism [insulin resistance]. 19) It is biologically plausible that in-utero MF exposure have an adverse effecton fetal development including the metabolic and endocrine systems. 20) Both maternal high BMI and diabetes are known risk factors for childhoodobesity/overweight, and the association between in-utero MF exposure andchildhood obesity was much stronger in the presence of these known risk factors. 21) In conclusion, our study provides the first epidemiologic link between in-utero MF exposure and childhood obesity/overweight. Given the worldwide epidemicof childhood obesity and ubiquitous MF exposure, this finding, could haveimplications for possibly reducing childhood obesity and understanding the obesityepidemic. 22) Prenatal exposure to high MF level was associated with increased risk ofbeing obese in offspring than those with lower MF level [69% increased risk]. Theassociation demonstrated a dose-response relationship and was stronger (morethan 2.3 fold increased risk) among children who were followed up to the end of thestudy. 23) Maternal exposure to high MF during pregnancy may be a new andpreviously unknown factor contributing to the world-wide epidemic of childhoodobesity/overweight.