Soy Formula May Harm Babies With Underactive Thyroid, University of California, San Diego (UCSD) Study  
8/22/2012 7:17:29 AM

Babies born with congenital hypothyroidism -- a condition that causes low or no thyroid hormone production -- shouldn't be given soy formula, new research indicates. Soy can interfere with the absorption of levothyroxine, the medication that replaces the missing thyroid hormone. If babies and toddlers don't get enough replacement thyroid medication, their brains can't develop properly, experts note.