If you drink tea, a recent study published in the scientific journal Environment International might cause you to reconsider the habit.
Researchers at the University of Southern California’s Keck School of Medicine have found a link between consuming certain types of foods and having higher blood levels of per- and polyfluoroalkyl substances, or PFAS.
Often known as “forever chemicals” — because they take a long time to break down and thus can build up in your body — PFAS are found in many fabrics, furniture and other items around the house. But the USC researchers also found that some dietary choices can result in higher levels of PFAS in the body.
Specifically, consuming higher levels of the following types of foods is associated with having higher levels of PFAS in your blood:
- Processed meats, such as hot dogs
- Foods prepared outside the home
In a summary of the findings, lead author Hailey Hampson, a doctoral student in the Keck School of Medicine’s Division of Environmental Health, says:
“We’re starting to see that even foods that are metabolically quite healthy can be contaminated with PFAS. These findings highlight the need to look at what constitutes ‘healthy’ food in a different way.”
As part of the study, more than 700 young adults were asked questions about their diet, and how often they eat in restaurants. Participants also gave blood samples that were tested for levels of PFAS.
As a general rule, those who ate more home-prepared meals had lower levels of PFAS than those who ate in restaurants. Food prepared in restaurants often comes into contact with food packaging, which can be made with PFAS.
For example, fast food containers and wrappers and grease-resistant paper are often made with PFAS, according to the U.S. Environmental Protection Agency (EPA).
Study participants who consumed higher levels of tea also had higher levels of PFAS. The researchers say PFAS in tea could come from several sources, but they note that tea bags are primarily made of paper, a major source of PFAS contamination. They conclude:
“Therefore, it is plausible that PFAS in tea bags may be contributing to the associations seen with tea intake. Previous studies have also seen that tea bags may be an exposure source for a variety of microplastics and nano plastics due to the brewing process with water at high temperatures … suggesting this could also be the case for PFAS contamination in tea.”
The USC scientists are now conducting follow-up research on PFAS in popular brands of tea.
The Environmental Protection Agency says exposure to PFAS can lead to a variety of health problems, including:
- Decreased fertility and increased high blood pressure in women
- Developmental effects and delays in children, including low birth weight and accelerated puberty
- Higher risk of cancers of the prostate, kidneys and testicles
- Reduced ability of the immune system to fight infections and reduced vaccine response
- Higher cholesterol levels and increased risk of obesity