Is 25-Hydroxycholesterol legal in the United States?

A cholesterol metabolite the body makes itself, reported in 2025 to reduce aortic stiffness in old mice as effectively as genetic clearance of senescent cells. Other work in mice points the opposite way in the brain, where the same molecule drives neuroinflammation.

25-Hydroxycholesterol is an oxysterol produced from cholesterol by the enzyme cholesterol 25-hydroxylase, which immune cells switch on during inflammatory activation. It is a signalling molecule, not a drug: it regulates sterol synthesis, interferon responses and inflammatory signalling.

Mechanism: Established in mice and cells: 25-hydroxycholesterol is made by cholesterol 25-hydroxylase, suppresses SREBP-driven cholesterol synthesis, and modulates interferon and inflammatory signalling. In the aortic study, the senolytic reading rests on the absence of any additional stiffness reduction in aortas from mice whose senescent cells had already been cleared genetically, plus suppression of its putative target CRYAB.

Regulatory history: Not approved for any indication. An endogenous metabolite sold as a laboratory reagent. No human trial is registered.

Approves prescription drugs by indication and polices unapproved products, including peptides sold online. Compounding pharmacies may prepare some compounds under a prescription when the FDA places them on a permitted bulk-substances category.

The classification above is the The Longevity Archive reading of U.S. Food and Drug Administration listings for 25-Hydroxycholesterol at the reviewed date, not a legal opinion. Rules change, and importing, prescribing and possessing a compound can each be treated differently. Check the regulator directly before acting on anything here.