Limited evidenceLongevity & antioxidants

Tetrahydrocurcumin

A colourless metabolite of curcumin, produced in the gut and sold as a supposedly more bioavailable and more antioxidant alternative. Human evidence amounts to one tiny pilot trial.

Evidence last reviewed: August 2026

What the science says

Depression as an add-on Limited evidence
A randomised open-label pilot trial in 19 patients with major depressive disorder compared escitalopram alone with escitalopram plus 200 mg/day tetrahydrocurcumin. With 19 participants and no blinding of treatment, this is a preliminary signal rather than a result.
Metabolic and antioxidant effects Limited evidence
Reviews of curcumin metabolites describe effects on glucose and lipid regulation and stronger antioxidant activity than curcumin itself in laboratory assays. Essentially all of this work is in cells and rodents.
Bioavailability advantage Limited evidence
The claim that supplemental tetrahydrocurcumin achieves better exposure than curcumin has not been demonstrated in a head-to-head human pharmacokinetic trial. Most published bioavailability comparisons involve formulated curcumin products, not tetrahydrocurcumin.

Dosage & safety

Studied doseNo established dose. The single clinical study used 200 mg/day; commercial products typically supply 250-500 mg/day as a label dose without trial support.

SafetyLittle human safety data beyond the very small trial, where no serious events were reported. By analogy with curcumin, expect possible gastrointestinal upset, and note that curcuminoids inhibit platelet aggregation and several CYP enzymes, so caution with anticoagulants and with drugs having a narrow therapeutic window. Turmeric and curcumin products have been associated with rare cases of liver injury. Avoid in pregnancy and with bile duct obstruction.

Scientific references

Tetrahydrocurcumin for Major Depressive Disorder with Therapeutic Potential and Mechanistic Insights from Clinical and Preclinical Studies
Guo Y, Xie J, Luo H — Mol Neurobiol, 2025
Curcumin Metabolites and Metabolic Health: Insights into Regulatory Mechanisms of Glucose and Lipid Homeostasis
Liu F, Zhao C, Zhang Q — Am J Chin Med, 2026

Where to buy

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