A new study has uncovered a link between the synthetic thyroid hormone (trade name Synthroid) used to treat millions diagnosed with Thyroid Diseases, bringing to the forefront the harmful role that overdiagnosis and overtreatment plays in nutritional deficiency and chemical exposure related ‘diseases.’A new Italian study published in the journal Reproductive Biology and Endocrinologytitled, “Levothyroxine and lung cancer in females: the importance of oxidative stress,” has raised a concerning possibility: levothyroxine (T4), one of the world’s most commonly prescribed forms of hormone replacement, may be raising the risk of lung cancer in millions of men and women being treated for Thyroid Diseases.
The authors of the study pointed out that levothyroxine (T4) treatment can lead to medication-induced (iatrogenic) thyroid over-activity (hyperthyroidism) and oxidative stress that can lead to a significant patient discomfort. They also noted that oxidative stress is one of the causes of chronic diseases and cancer.The study looked at the prevalence of breast, colorectal, gastric and lung cancer in 18 Italian Regions during 2010 and correlated this data with sales of LT4 in 2009, focusing on women aged 30-84. (They noted that this age range corresponds to more than 80% of the consumers of the drug and to about 99% of all malignant cancers). They then correlated drug sales with cancers, eliminating the contribution of age and smoking for lung cancer risk. They found no significant correlation between T4 sales and breast, colorectal and gastric cancers, but did find a significant correlation for lung cancer(p < 0.05) corrected for smoking and age.