The Microplastics Cleanse

April 8, 2026·31 min·2 clips

A study found microplastic accumulation in human brain tissue was 10 times higher in dementia cases than in tissue from people without dementia.

1. Outside/In producer Halima Shah investigates the microplastics cleanse trend, testing her own blood and examining the science and commerce behind detox claims. 2. Shah is the reporter and primary voice; host Nate Hedgie co-presents, and guests include Dr. Marcus Garcia of the University of New Mexico, Clarify Clinics CEO Yale Cohen, and law professor Sarah Marath of Wake Forest University. 3. The episode asks whether personal microplastics treatments are a legitimate health response or expensive, unproven products filling a gap left by incomplete science. 4. Shah pays $360 for a finger-prick blood test from Blueprint, the longevity company founded by Brian Johnson, who describes a daily routine of red light therapy, hyperbaric oxygen therapy, and sauna. 5. Before getting her results, Shah visits the National Aquarium in Baltimore to see microplastics in the wild, wading through an urban marsh with conservation director Charmaine Dolling, who finds colorful microplastic confetti lining the grasses each morning. 6. Dr. Marcus Garcia co-authored a study in Nature Medicine analyzing brain, kidney, and liver tissue from over 50 cadavers and found brain tissue had the highest concentration of micro and nanoplastics. 7. The study's most alarming finding was that dementia cases had 10 times the plastic accumulation compared to normal tissue, though Garcia explicitly frames this as correlation, not causation. 8. Nine scientists published rebuttals in the same Nature Medicine issue, with one bioanalytical researcher calling the study 'a joke' and citing fat tissue's tendency to trigger false positives for polyethylene. 9. A separate Italian study suggested people with microplastics in a key artery were more likely to suffer stroke or heart attack, though that study was also contested for its methodology. 10. TikTok wellness creators promote supplements — apple pectin, lactobacillus plantarum, sulforaphane from broccoli, psyllium husk fiber — as ways to excrete microplastics, along with sauna sessions three to four times a week. 11. Garcia told Shah that sauna evidence for microplastic removal is thin, but fiber increasing bowel frequency might help clear larger microplastic particles; nanoplastics may be too small to excrete and could be absorbed by organs instead. 12. A Stanford scientist studying plastics and human health told Shah that wellness solutions filling research gaps are 'a way for people to make money off of our fears,' and supplements are not FDA regulated. 13. Yale Cohen, CEO of Clarify Clinics, describes Clary as an apheresis procedure: blood is drawn through a tube, separated in a centrifuge, and returned minus the supposedly harmful components, over a four-hour session. 14. Clarify Clinics operates in London, Dubai, and Johannesburg but is not FDA-approved in the United States; the procedure costs $13,000 and is not covered by insurance. 15. Critics note the procedure's own tubing is plastic, potentially introducing microplastics into the blood it is meant to clean, and if plastics accumulate in organs like the brain, filtering the blood may not address the primary burden. 16. Orlando Bloom has publicly endorsed Clary, and the procedure received prominent coverage in The Cut, generating significant public attention before peer-reviewed evidence of efficacy exists. 17. The episode has a conversational, inquiry-driven format; Shah personally undergoes the test and reads her results live to Nate, giving the story a first-person accountability thread. 18. Tone is skeptical but not dismissive — Shah takes the science seriously, grants the experts nuance, and acknowledges her own anxiety while remaining journalistically grounded. 19. Listeners interested in environmental health, wellness industry criticism, or the gap between scientific uncertainty and consumer behavior will find this episode directly relevant. 20. Listeners who want definitive health guidance or are already committed to a microplastics supplement regimen may find the episode's conclusion — that the science is too uncertain to know what works — unsatisfying.

As heard by us

A careful look at microplastics, home testing, and the wellness claims built around them.

Outside/In turns an ordinary plastic habit into a quietly unnerving question: what is this material doing inside us? Nate Hedgie and Halima Shah begin with the things people touch every day - takeout boxes, Amazon packaging, cutting boards, Teflon - and move into the newer…

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You want the microplastics detox hype checked, not echoed.

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