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Associations Between Perfluoroalkyl Substances And Lipid Profile In A Highly Exposed Young Adult Population In The Veneto Region, Environment International, September 2020

PFAS were associated with an increased probability of having abnormal levels of TC [total cholesterol], non-HDL-Cholesterol, and LDL-Cholesterol.
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PFAS have structural similarities with fatty acids and may interfere with fatty acid metabolism and lipid synthesis in the liver.
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Conclusions: Investigation of the shape of exposure-response associations using splines showed a positive association with the largest increases per unit of PFAS in cholesterol levels occurring at the lower range of PFAS concentrations for each compound.

They controlled for diet.

This was in Italy. The amount of PFAS in tap water across the US varies. But it’s quite high in some places. And it is increasing everywhere. Unless your water treatment plant filters to remove PFAS (an expensive proposition and not done at most municiple treatment facilities right now) you can’t be sure your water is unaffected.

Also, one’s exposure to PFAS is not via water alone. Food (packaging chemicals leak into food and PFAS bioaccumulates in animal tissue), air, and skin are alternative routes. Do you stand at the sink washing dishes? Do you take showers? You were exposed. Even if the exposure was small, PFAS are “forever chemicals”, they don’t break down in the body, they accumulate. CDC’s studies show that the blood of nearly all Americans is contaminated with PFAS.