Limited evidenceStress & mood

Phellodendron Bark

Sold almost exclusively paired with magnolia bark in a proprietary extract marketed for cortisol and stress. Two small, industry-funded trials found modest effects; nothing larger has confirmed them.

Evidence last reviewed: August 2026

What the science says

Perceived stress and cortisol Limited evidence
A 6-week double-blind trial in 40 moderately stressed adults using a magnolia-phellodendron extract reported lower salivary cortisol and better mood scores than placebo. The sample was small and the study was funded by the ingredient manufacturer.
Stress in healthy women Limited evidence
A pilot double-blind placebo-controlled trial in 28 premenopausal women found a reduction in a transient anxiety scale but no significant change in cortisol or overall stress questionnaires. The authors described the result as preliminary.
Weight and stress-related eating Limited evidence
A pilot double-blind trial in overweight women reported that the extract prevented weight gain relative to placebo over 6 weeks, without an effect on cortisol. This finding has not been replicated in a larger trial.

Dosage & safety

Studied doseTrials used a proprietary magnolia + phellodendron extract at 500–750 mg/day, taken in two to three divided doses. There is no established dose for phellodendron bark alone.

SafetyShort-term trials reported mild side effects such as drowsiness, heartburn and headache. Phellodendron contains berberine, which can inhibit CYP enzymes and interact with many drugs and which should be avoided in pregnancy, breastfeeding and in newborns. Data beyond a few weeks of use are lacking.

Scientific references

Effect of a proprietary Magnolia and Phellodendron extract on stress levels in healthy women: a pilot, double-blind, placebo-controlled clinical trial
Kalman DS, Feldman S, Feldman R — Nutr J, 2008
Effect of Magnolia officinalis and Phellodendron amurense (Relora®) on cortisol and psychological mood state in moderately stressed subjects
Talbott SM, Talbott JA, Pugh M — J Int Soc Sports Nutr, 2013
Effect of a proprietary Magnolia and Phellodendron extract on weight management: a pilot, double-blind, placebo-controlled clinical trial
Garrison R, Chambliss WG — Altern Ther Health Med, 2006

Where to buy

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