14 DAY TRIAL // Now we have finally found out why some people can be registered as qualified skunks and why some of our workmates subdue us daily to olfactive tortures!
Look why: Phthalates are esters widely used for over 50 years in everything from plastics (to turn them flexible), PVC, soaps, cosmetics, shampoos, lotions, lubricants, paint to the coating of some timed-release medicines.
Over 75 % of the US population presents detectable levels of several phthalates in the urine.
Recently, a team at the University of Rochester Medical Center found that exposure to phthalates, already linked to reproductive problems, has been connected to abdominal obesity and insulin resistance in adult men. "The research adds to the growing suspicion that low-dose exposures to phthalates and other common chemicals may be reducing testosterone levels or function in men, and thereby contributing to rising obesity rates and an epidemic of related disorders, such as Type 2 diabetes," said lead author Dr. Richard Stahlhut, a Preventive Medicine resident.
"Substantial declines in testosterone levels and sperm quality have been observed in the United States and other countries over the last several decades which and it urgently requires explanation. While we can't say yet that phthalates are a definite cause, I am certain they are on the list of chemicals that demands careful study."
Animal and human experiments have revealed that phthalates decrease males' testosterone levels and semen quality and induce subtle changes in the genitalia of little boys. "This connection between phthalates and testosterone helped to establish a basis for the study," said Stahlhut.
Low testosterone level is known to boost the belly fat and pre-diabetes in men. So the team investigated urine, blood samples and other data ranging from 1999 to 2002 from the National Health and Nutrition Examination Survey from 1999 to 2002, focusing on phthalates levels.
Based on these data, 1,451 adult men had records on phthalate exposures, obesity and waist circumference and 651 on fasting glucose and insulin levels (for assessing insulin resistance).
The investigation found that several phthalate metabolites were connected to abdominal obesity. Males with the highest phthalate levels in their urine presented more belly fat and insulin resistance. Other influencing factors like men's age, race, food intake, physical activity levels and smoking were adjusted. "Unfortunately, there's still a lot to learn about phthalates. The more difficult issue is what combinations of common low-dose chemical exposures might be contributing to these problems", Stahlhut said.