They're in thousands of everyday products and scientists say the "forever chemicals" used to repel oil, water and stains may be quietly putting teenagers at greater risk for a serious liver condition.
Per- and polyfluoroalkyl substances (PFAS) have already been linked to a range of health problems, including certain cancers, immune system harm and birth defects.
But a new study suggests that exposure to the man-made chemicals during adolescence may sharply raise the risk of metabolic dysfunction-associated steatotic liver disease (MASLD), a potentially dangerous condition that often goes undetected until significant damage is done.
PFAS do not break down easily, meaning they can persist in the environment for years, contaminating drinking water, soil, air and wildlife.
Researchers say that widespread contamination has made exposure nearly unavoidable, with more than 98% of Americans carrying detectable PFAS levels in their blood.
In the study, researchers analyzed 284 adolescents and young adults from Southern California who were participants in two long-term studies conducted by the University of Southern California's Keck School of Medicine.
The team tested participants' blood for PFAS levels and used MRI scans to measure fat buildup in their livers.
Higher levels of two common PFAS — perfluorooctanoic acid (PFOA) and perfluoroheptanoic acid (PFHpA) — were associated with a significantly greater risk of developing MASLD.
The disease, formerly known as nonalcoholic fatty liver disease, occurs when excess fat accumulates in the liver and is often linked to obesity, type 2 diabetes, high blood pressure and high cholesterol.
But researchers found the link was strongest in teenagers, not young adults.
"Adolescents are particularly more vulnerable to the health effects of PFAS as it is a critical period of development and growth," Dr. Shiwen "Sherlock" Li, the study's lead author, said in a press release.
Teens with double the amount of PFOA in their blood were nearly three times more likely to have MASLD, the researchers found.
The danger appeared even greater for adolescents with a genetic variant known as PNPLA3 GG, which affects how the liver stores fat. Among young adults, smoking further worsened PFAS-related liver damage.
"These findings suggest that PFAS exposures, genetics and lifestyle factors work together to influence who has greater risk of developing MASLD as a function of your life stage," Dr. Max Aung said.
The findings come as MASLD rates are expected to rise. About 10% of U.S. children are currently affected, but that figure jumps to nearly 40% among children with obesity, according to the American Liver Foundation.
MASLD can progress silently for years before leading to serious complications, including heart disease, fibrosis, cirrhosis and liver cancer. Lifestyle changes — including a healthier diet, more physical activity and weight loss — can slow or even reverse liver damage, especially when caught early.
Nicole Weatherholtz ✉
Nicole Weatherholtz, a Newsmax general assignment reporter covers news, politics, and culture. She is a National Newspaper Association award-winning journalist.
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