Chemical in Cosmetics Could Cause Thyroid Fluctuations

Some cosmetics could be carrying chemicals that can cause dangerous changes in thyroid function, according to a new study.

The harmful chemical found in cosmetics is known as perfluorinated chemicals (PFCs) and can be used to manufacture items such as fabrics, carpets, cosmetics and paper coatings. As these chemicals break down very slowly, they also take a long time to leave the body and could result in hidden health hazards. 

Researchers first analyzed data from more than 1,100 people who took part in the 2007-2008 and 2009-2010 U.S. National Health and Nutrition Examination Survey. The study also looked at levels of four different PFCs as well as participants' thyroid function.

Results showed that those with higher levels of PFCs in the body also had altered thyroid function, with an increased risk of mild hypothyroidism in women.

The Mayo Clinic defines hypothyroidism as a condition in which the thyroid gland doesn't produce enough of certain important hormones. Though more commonly seen in women over 60, the health problem upsets the normal balance of chemical reactions in the body that can lead to other health issues, including obesity, joint pain, infertility and heart disease.

"Our study is the first to link PFC levels in the blood with changes in thyroidfunction using a nationally representative survey of American adults," study co-author Dr. Chien-Yu Lin, of En Chu Kong Hospital in Taiwan, said in a journal news release.

Researchers said primary concerns regarding the chemical is how long it stays in the body and what long-term effects could be seen on human health.

More information regarding the study can be found in the Journal of Clinical Endocrinology & Metabolism.