Your PFAS blood test came back high. What should you do?

What your number means

Start with the breakdown of individual PFAS compounds on your report. The National Academy of Sciences adds seven of them together and uses the total to guide follow-up care across three bands:

A detectable PFAS result isn’t unusual. Nearly everyone in the US has some in their blood. CDC testing has detected PFAS in more than 98% of blood samples from the general US population. A total above 2 ng/mL is a reason to look closely at possible exposure sources, especially drinking water and work.

The total is only part of the picture because individual PFAS compounds behave differently in the body. For example, the World Health Organization’s cancer agency classifies PFOA as carcinogenic to humans and PFOS as possibly carcinogenic. This is why we developed the Tare Score^™, a single score you can track over time that assigns different weights to PFAS compounds based on their persistence and health risks.

Keep it in perspective

Large population studies have linked PFAS to higher cholesterol, weaker responses to vaccines, kidney cancer, testicular cancer, and other conditions. The Science lists those studies. Those findings tell us about risks across populations, not what will happen to any one person. And while lowering PFAS in blood is measurable, researchers haven’t yet shown in a clinical trial that it prevents a particular disease.

Without treatment, it can take years for your PFAS levels to fall by half.

Four steps to take next

1. Start with a physician consult. The National Academies guidelines give clinicians a follow-up plan for each band. At 2 to under 20 ng/mL, the guidelines call for reducing known exposure and prioritizing cholesterol screening, along with pregnancy-related and breast cancer screening as appropriate. At 20 ng/mL or higher, follow-up also includes thyroid testing and checks for signs of kidney cancer, testicular cancer, and ulcerative colitis, according to age. If you use Tare, you can go straight to a physician consult with a doctor who’s familiar with this space and takes your concerns seriously from the beginning.
2. Stop new exposure. Drinking water is one important source to check, especially in areas with known contamination. A certified activated-carbon or reverse-osmosis filter removes much of the PFAS from tap water. If you’re on a private well in an affected area, have the well tested before you choose a filter. A filter can cut what you take in from water. It can’t remove PFAS already circulating in your blood.
3. Lower the PFAS already in your blood. Your body clears PFAS slowly because your gut keeps recycling them back into your blood. Prescription medications called bile acid sequestrants bind PFAS in the gut so they leave in stool instead. In a 2025 clinical trial, blood PFAS fell 2 to 20 times faster during treatment than without it. Several other published studies have reported similar findings, adding to the evidence that bile acid sequestrants can speed PFAS clearance. You can explore that research on The Science page. For a fuller explanation of the options, read our guide to lowering PFAS levels.
4. Retest. Only another test can show whether your levels are falling. If you’re on treatment, retest after three months. Stick with the same type of test so you can make a meaningful comparison.