German food safety panel warns CBD supplements may cause liver harm without proven benefits | Research

The takeaway

A German food safety commission found that CBD supplement doses commonly available on the market can reach levels linked to liver enzyme elevations, while no health claims were supported at safe doses.

CBD supplement consumers, healthcare providers advising on supplement use, and regulators overseeing novel food products.

Liver harm threshold of 4.3 mg/kg/day reachable with 30 drops of 20% CBD oil

What the researchers found

The lowest dose tested in humans that caused adverse effects (liver enzyme elevations) was 4.3 mg/kg/day, and this level can easily be reached by following the dosage recommendations on commercially available CBD oil products.

Why it matters

Despite having no Novel Food authorization in the EU, CBD products are widely sold with health claims. This review suggests consumers may be reaching harmful doses while getting no proven benefit.

The numbers in context

LOAEL for liver toxicity: 4.3 mg/kg bw/day (healthy volunteers, 3-4 weeks). This level is reachable with 30 drops of 20% CBD oil. No NOAEL could be established because lower doses were not tested. No health claims substantiated at or below the LOAEL.

How the study worked

Expert review by Germany's Permanent Senate Commission on Food Safety evaluating available data on CBD's adverse effects and potential health benefits at food-relevant doses.

What this study cannot tell us

The LOAEL was based on limited human studies. Lower doses were not tested, so a safe threshold could not be established. The review focused on food-relevant doses, not pharmaceutical CBD (Epidyolex) which uses much higher doses.

How to read the evidence

Expert regulatory review synthesizing available human and preclinical data. Limited by the small number of dose-ranging studies in healthy volunteers.

When this study was published

Published in 2025.

The bigger picture

The CBD supplement market has grown faster than the safety research supporting it. This regulatory assessment adds to concerns that consumer products may carry underappreciated risks, particularly for liver health.

Questions still open

What is the true no-effect level for CBD liver toxicity? Are certain populations (e.g., those on medications metabolized by the liver) at higher risk?

Common questions

Can CBD supplements harm your liver?

This review found that liver enzyme elevations occurred at 4.3 mg/kg/day in healthy volunteers, a dose easily reached with common CBD oil products. Because lower doses were not tested, a safe threshold is unknown.

Do CBD food supplements have proven health benefits?

The German food safety commission found no scientific evidence supporting health claims for CBD at doses at or below the level that causes liver changes, including claims about anxiety, sleep, pain, and stress.

Read the original research

Cannabidiol in Foods and Food Supplements: Evaluation of Health Risks and Health Claims.

Nutrients, 17(3)

View on PubMed ↗Publisher’s paper ↗

Citation

Engeli, Barbara E; Lachenmeier, Dirk W; Diel, Patrick; Guth, Sabine; Villar Fernandez, Maria A; Roth, Angelika; Lampen, Alfonso; Cartus, Alexander T; Wätjen, Wim; Hengstler, Jan G; Mally, Angela. (2025). Cannabidiol in Foods and Food Supplements: Evaluation of Health Risks and Health Claims.. Nutrients, 17(3). https://doi.org/10.3390/nu17030489