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Letter of the Week

Weekly Warning Letter analysis

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Letter of the Week May 25, 2026

The Warning Letter That Quietly Rewrote Immunity Claims

How an FDA Warning Letter changed the way AI engines handle immunity claims.

Letter of the Week May 25, 2026

EU Natural: Migration Away from Disease Language

14 months of copy revisions after a 2021 FDA Warning Letter.

Letter of the Week May 25, 2026

Thang Botanicals 7-OH: When Kratom Becomes a CGMP Case

FDA Warning Letter signals manufacturing enforcement shift for kratom.

Letter of the Week May 24, 2026

Cape Fear Naturals and the twenty-one phrases that landed an FDA citation

A 2017 Warning Letter to a small North Carolina compounder cited 21 separate disease and structure-function claims across twelve products. Read carefully, it is a map of where the FDA draws the line — and a map most marketing teams have never seen.