The Claim
Higher placental transfer efficiency of arsenic, mercury, manganese, zinc, selenium, cobalt, copper, and iron is associated with elevated neonatal thyroid-stimulating hormone (TSH) levels, and higher placental transfer efficiency of manganese, copper, and iron is associated with reduced neonatal free thyroxine (FT4) levels.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When more of certain metals and minerals pass from mother to fetus through the placenta, newborns may have higher levels of thyroid-stimulating hormone and lower levels of free thyroxine, which are indicators of altered thyroid hormone regulation.
See the scientific wording
Higher placental transfer efficiency of arsenic, mercury, manganese, zinc, selenium, cobalt, copper, and iron is associated with elevated neonatal thyroid-stimulating hormone (TSH) levels, while higher placental transfer efficiency of manganese, copper, and iron is associated with reduced neonatal free thyroxine (FT4) levels, suggesting that fetal exposure to these metals via placental transport may disrupt thyroid hormone regulation in newborns.
What the research says
1 studyThe study found that when more of these metals pass from mom to baby through the placenta, the baby’s thyroid hormones get disrupted—some go up, some go down—just like the claim said.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.