Are we hurting our noggins? Internationally, are there social customs, diseases, pollutants, school policies, parental choices, drugs, diets and philosophies that cause, or are correlated with, decreased intelligence?
Here are fourscore-and-a-trio of the mind-mangling menaces. A preponderance of the fearsome factors have undergone scientific scrutiny, with statistics filed in the massive archives of pubmed.gov.
Prenatal – Damaged before you’re delivered
Cousin Marriages – “Consanguineous” marriages between cousins or relatives more than triples the rate of mental retardation. One study shows an average IQ drop of 7 points; another reveals a loss of 11.2 points.
Avoiding PreNatal Diagnosis – Fetal Screening can determine if fetuses have birth defects or genetic diseases that cause cognitive damage. Recommended for older parents and those carrying genes of genetic disorders.
Prenatal Iodine Deficiency – The World Health Organization says iodine deficiency is the “single greatest preventable cause of mental retardation.” Average deduction is 10-17 IQ points.
Prenatal Folic Acid Deficiency – Infants with neural tube defects suffer a loss of 15 IQ points.
Prenatal Choline Deficiency – Can wreck spatial memory and hippocampal plasticity in adulthood.
Fetal Alcohol Syndrome (Heavy Alcohol Exposure) – Children afflicted with fetal alcohol syndrome have an average IQ of 75.
Moderate Prenatal Alcohol Exposure – Gestating women who imbibe two alcoholic drinks per day hamper their child’s IQ with a 7-point loss.
Pesticide Exposure – Prenatal (and postnatal) exposure to organophosphate pesticides can cause a deficit of 7.0 IQ points.
Prenatal Cigarette Exposure – Loss of IQ is reported as 3.3, 6.2, and 15 points in various studies.
Prenatal Hydrocarbons (Smog) Exposure – Two studies showed IQ losses of 4.31 and 3.8 points.
Prenatal Cocaine Exposure – Boys exposed to cocaine had lower IQs at 4, 6, and 9 years of age.
Prenatal Methamphetamine Exposure – Meth exposure leads to weakened verbal memory, and damage to visual motor integration, attention, and long-term spatial memory.
Embryonic Malnutrition – Multiple infants sharing a womb are at risk of suboptimal nutrition. Lighter twins have verbal IQ that’s 7.5 points lower than heavier twins.
Maternal Stress – Children exposed to high cortisol levels in the womb, caused by maternal stress, suffer an average verbal IQ loss of 3.83 points.
Prenatal Valproate Exposure – Embryos exposed to Valproate have IQ scores up to 9 points lower than children exposed to other anti-epileptic medications.
Prenatal Excess Mercury Exposure – Reports vary, but one study concluded that excessive prenatal intake of mercury in fish costs children 1.5 points in IQ.
Prenatal Radiation Exposure – Embryos exposed to radiation had more speech-language disorders, emotional disorders, and borderline IQ.
Premature Birth – Babies delivered before 40 weeks have smaller heads and an IQ 4.9 points lower than infants delivered after 40+ weeks.
Breech Birth – Males born via breech birth have a 7-point lower IQ than boys who were born in cephalic presentation.
Compiled by Hank Pellissier. Continue at The Institute for Ethics and Emerging Technologies