Green tea supplements and liver injury in U.S. patients
What it found
In a U.S. study of people with liver injury, 40 cases were attributed to green tea supplements, often severe and linked to a specific immune gene.
The injury typically appeared 1 to 6 months after starting the supplement.
What they found
Studies in people
Frequency of green tea injury
Among 1,414 patients with drug-induced liver injury, 40 cases (3%) were attributed to green tea. Green tea accounted for 15% of dietary supplement-related cases.
Symptoms and timing
Patients with green tea liver injury ranged in age from 17 to 69 years (median 40) and developed symptoms 15 to 448 days (median 72) after starting the implicated agent. Most were jaundiced (83%) and symptomatic (88%).
Severity and outcomes
The course was judged severe in 14 patients (35%), and 3 (8%) needed a liver transplant. Chronic injury was rare (3%).
HLA-B*35:01 link
HLA-B*35:01 was found in 72% of green tea cases, compared with 15% of other supplement cases, 12% of drug cases, and 11% of population controls. The authors say this suggests the injury is idiosyncratic and immune mediated.
Recurrence on re-exposure
In three instances, liver injury recurred upon re-exposure to green tea, with similar clinical features but shorter time to onset.
Other findings
Product analysis
Chemical analysis of 16 products found green tea catechins in all but one. The amount per serving ranged from 6.6 to 384 mg.
What the authors conclude
“Green tea-related liver injury has distinctive clinical features and close association with HLA-B*35:01, suggesting that it is idiosyncratic and immune mediated.”
Also in their conclusions
- They conclude that green tea-related liver injury has distinctive clinical features and a close association with HLA-B*35:01.
- They suggest that the injury is idiosyncratic and immune mediated.
- They advise that HLA-B*35:01 may be helpful in diagnosis and provide new insights for research.
How it was done
Herbal supplements are increasingly common causes of acute liver injury, and green tea is a frequent component in implicated products, but its role in liver injury is controversial. The authors wanted to better characterize the clinical features, outcomes, and pathogenesis of green tea-associated liver injury.
They analyzed 1,414 patients enrolled in the U.S. Drug-Induced Liver Injury Network between 2004 and 2018 who had undergone causality assessment. They identified 40 cases attributed to green tea, compared them with 202 cases from other dietary supplements and 1,142 from conventional drugs, and performed HLA typing on 36 of the green tea cases and controls.
What it can’t tell you
- This study looked at people who already had liver injury, so it cannot show how often green tea supplements cause liver injury in all users.
- It cannot prove that green tea causes liver injury in any individual, only that the cases were attributed to it after expert review.
- The link with HLA-B*35:01 does not mean that everyone with this gene will develop liver injury from green tea.
Who paid
- Funding
- Funded by NIDDK NIH HHS; NIGMS NIH HHS (from the PubMed record).
- Authors work at
- National Institute of Diabetes and Digestive and Kidney Diseases, MD; National Cancer Institute, MD; Wake Forest University School of Medicine, NC
The paper
- Title
- HLA-B*35:01 and Green Tea-Induced Liver Injury
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Hoofnagle JH, Bonkovsky HL, Phillips EJ, et al (2021). HLA-B*35:01 and Green Tea-Induced Liver Injury. Hepatology (Baltimore, Md.). doi:10.1002/hep.31538Free full textPubMed 32892374DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error