Human study

Liver function


Cannabis and Cannabinoid Research.Feb 2023.148-154.

Article name

Observed Impact of Long-Term Consumption of Oral Cannabidiol on Liver Function in Healthy Adults.


Robert Kaufmann, Keith Aqua, Jeff Lombardo, and Martin Lee.

The Effects of Long-Term CBD Use on Liver Function in Healthy Adults

This study, titled "Observed Impact of Long-Term Consumption of Oral Cannabidiol on Liver Function in Healthy Adults", is an observational study conducted on adults across the United States. The participants were self-administering CBD for at least 30 days. The study was not conducted in a lab, but rather, the participants were recruited from various CBD product companies.

About the Authors and Their Institution

The study was conducted by Robert Kaufmann, Keith Aqua, Jeff Lombardo, and Martin Lee, and was published in the Cannabis and Cannabinoid Research journal. The research was decentralized, meaning it was conducted across various locations rather than in a single lab or institution.

Main Findings

  • The prevalence of elevated liver tests (LT) was not significantly different from the general adult population.
  • There was no significant association between CBD dosage and LT values.
  • Most of the LT elevations are likely due to the conditions/medications for which the individuals are taking CBD.

A Closer Look at the Methodology

The study involved adults aged 18-75 years who had been taking CBD orally for a minimum of 30 days. The data was collected using an app-based clinical study platform, which collected demographic information, medical history, reasons for taking CBD, dosage, current medications, adverse effects, and efficacy. After 30 days, liver tests were conducted. The daily dose of CBD was 50.3±40.7 mg.

Potential Implications

The findings suggest that self-medication of CBD does not appear to be associated with an increased prevalence of liver test elevation. This could have significant implications for the use of CBD products in managing various health conditions.

What are the Limitations of this Study?

One limitation of the study is that it was observational and decentralized, which means there might be variations in data collection. Also, the participants were self-administering CBD, which could lead to variations in dosage and administration methods.


Overall, the study suggests that long-term consumption of CBD does not appear to significantly impact liver function in healthy adults. However, more research is needed to confirm these findings and understand the long-term effects of CBD use.

Read the full study here.


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