PFA (Per- and Polyfluoroalkyl Substances) is something we love to hate. They are chemicals used in many industrial applications, such as clothing and plastics, due to their useful properties. Because of concerns that PFA may cause various human health issues, they are increasingly becoming the focus of epidemiological studies.
Additionally, PFA is somewhat concerning because it takes a long time to break down in the environment. This has led the media to label them as 'forever chemicals.' And according to recent headlines, these forever chemicals may reduce the risk of thyroid cancer in people.
Fortunately for all of us, the association between PFA and thyroid cancer is at best very weak. While it is not impossible for PFAS substances to cause problems with the thyroid, the evidence so far is unconvincing and probably not worth worrying about.
Science
The headlines that have emerged everywhere regarding PFA are based on a recently published new epidemiological study in the journal Ebiomedicine. In this study, researchers took individuals diagnosed with thyroid cancer who had undergone various blood tests before their diagnosis and compared them to some control groups without thyroid cancer.
After controlling for several factors, the researchers found a moderate correlation between one PFA, particularly N-PFO, and thyroid cancer. The adjusted odds ratio for this association was 1.56, meaning that the likelihood of having thyroid cancer was 56% higher for individuals with much higher levels of this substance in their blood.
This finding has led to many headlines about PFA causing cancer, but I think it is worth putting these results in the proper context before getting scared about this entirely new cancer risk. First, this study was truly small. The authors…