What researchers observed
The FDA’s August 2025 summary describes a 28-day randomized study involving 201 healthy adults. The study used an oral CBD solution totaling 250–550 mg daily, or placebo. These are research amounts, not suggested doses. Eight CBD participants developed ALT liver-enzyme elevations above three times the upper limit of normal; the study estimated a 5.6% risk. No placebo participants met that threshold. [1]
The changes occurred without liver-related symptoms and resolved after CBD was stopped. These laboratory findings should not be rewritten as “5.6% of all CBD users will develop liver disease.” That would change both the population and the outcome. [1]
What the finding can—and cannot—tell us
The study adds a reason to take safety assessment seriously even when a product feels mild. It does not identify a universal safe amount for self-directed use, and it does not predict an individual person’s outcome.
When reading a safety percentage, ask who was enrolled, which preparation was used, how long participants were followed, and which definition triggered a finding. Those details belong beside the number. They are part of understanding the research, not fine print to discard.
For this brief, we used the FDA investigators’ summary. We have not presented it as a complete review of all liver-safety research.
A useful next conversation
If you are considering CBD, tell your clinician about your health history, medicines, supplements, and the exact product. Ask whether there is a reason to avoid it and whether any monitoring would be appropriate for your situation.
Do not use a lack of immediate discomfort as your only test of safety. Equally, a research headline is not a diagnosis. A clinician can help interpret concerns without turning a study percentage into a prediction about you.
Our reading: this finding strengthens the case for individualized safety advice. It does not support a blanket claim that every CBD product causes the same harm.
Sources & scope
Sources consulted September 12, 2026. This article explains selected evidence; it is not an exhaustive literature review. Practical reading questions and interpretations are our editorial guidance.