Hepatitis C and Dietary Supplements: What the Science Says
Clinical Guidelines, Scientific Literature, Info for Patients:
Hepatitis C and Dietary Supplements
Dietary Supplements
No dietary supplement has been shown to be effective for hepatitis C. Several studies of silymarin (milk thistle) dietary supplements in people with hepatitis C did not find beneficial effects.
Milk Thistle
Current research suggests that milk thistle is no better than placebo as a treatment for hepatitis C.
What Does the Research Show?
- A 2017 systematic review and meta-analysis of a total of 23 trials evaluated the effect of silymarin on the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyl transpeptidase (γGT) in patients with liver diseases. The authors concluded that silymarin minimally reduced the serum levels of ALT and AST; however, the results were without clinical relevance. They also noted the need to conduct studies with more appropriate methodological designs.
- A 2014 meta-analysis of five randomized controlled trials found that the effects of silymarin on alanine aminotransferase (ALT) levels of patients with hepatitis C were similar to those of placebo; however, no beneficial effects were found for silymarin. Improvements in the quality of life of silymarin and placebo recipients were relatively identical.
- A 2012 controlled trial showed that two higher-than-usual doses of silymarin were no better than placebo in reducing alanine aminotransferase (ALT) levels in patients with chronic hepatitis C. Decreases in serum ALT levels are correlated with improvement in hepatic necroinflammatory activity after interferon therapy for hepatitis C.
- Findings from the 2008 uncontrolled HALT-C study suggest that silymarin use by hepatitis C patients was associated with fewer and milder symptoms of liver disease and somewhat better quality of life, but there was no beneficial effect found on serum ALT or hepatitis C virus RNA levels. It is important to note that the finding of improved quality of life in patients taking silymarin was not confirmed in the more rigorous 2012 study described above.
Safety
- Available evidence from clinical trials in people with liver diseases suggests that milk thistle is generally well-tolerated.
- Side effects can include a laxative effect, nausea, diarrhea, abdominal bloating and pain, and occasional allergic reactions.
Probiotics
Only a few studies have examined the effects of probiotics on hepatitis C, and of those studies, there isn’t any clear evidence that probiotics are helpful in people with hepatitis C.
What Does the Research Show?
- A 2014 randomized controlled trial involving 53 patients with chronic liver disease found that short-term probiotic administration is effective in alleviating small intestinal bacterial overgrowth and clinical symptoms, but ineffective in improving intestinal permeability and liver function.
Safety
- Most people can use probiotics without experiencing any side effects—or with only mild gastrointestinal side effects—but there have been some case reports of serious adverse effects in people with underlying serious health conditions.
Zinc
Preliminary studies, most of which were conducted outside the United States, have found that zinc supplements might help to correct zinc deficiencies associated with hepatitis C, reduce some symptoms, or improve patients’ response to treatment, but the evidence for these possible benefits is limited.
What Does the Research Show?
- A 2023 review of 12 studies concluded that data suggest that zinc supplementation in addition to other antiviral therapy is a viable treatment regimen for viral hepatitis; however, this needs to be further elucidated through large cohort-based clinical studies.
- A 2020 systematic review and meta-analysis of 13 studies (6 of which assessed chronic hepatitis C treatment) found a relative risk of 0.83 indicating no protective effect of zinc supplementation on the improvement of sustained virological response.
- A 2015 multicenter randomized controlled trial in 53 patients with hepatitis C found that branched-chain amino acids (BCAA) and zinc-enriched supplements reduced the serum α‑fetoprot (AFP) levels in patients who had elevated serum AFP levels at baseline. The authors of the study concluded that BCAA and zinc-enriched supplementation may prolong the survival of patients with hepatitis C by improving amino acid imbalance and zinc deficiency, and by partly down regulating AFP.
Safety
- Zinc is generally considered to be safe when used appropriately, but it can be toxic if taken in excessive amounts.
Glycyrrhizin
There is currently insufficient evidence to determine if glycyrrhizin is efficacious for hepatitis C.
What Does the Research Show?
- A 2012 randomized controlled trial in 379 patients with chronic hepatitis C who failed to respond to previous interferon-based therapies found that glycyrrhizin exhibited a significantly higher ALT reduction compared to placebo after 12 weeks of therapy and an improvement of necro-inflammation and fibrosis after 52 weeks of treatment.
Safety
- In large amounts, glycyrrhizin or licorice can be dangerous in people with a history of hypertension, renal failure, or cardiovascular diseases.
Other Dietary Supplements
- Preliminary studies have examined the potential of the following products for treating chronic hepatitis C: TJ-108 (a mixture of herbs used in Japanese Kampo medicine), oxymatrine (an extract from the sophora root), chlorella (a type of algae), black cumin (Nigella sativa), S-adenosyl-L-methionine (SAMe), and thymus extract (from cattle). The limited research on these products hasn’t produced convincing evidence that they’re helpful for hepatitis C.
- A few preliminary studies have looked at the effects of combining supplements such as lactoferrin, SAMe, or zinc with conventional drug therapy for hepatitis C. The evidence isn’t sufficient to draw clear conclusions about benefit or safety.
- Preliminary research has looked at substances that might reduce the risk of liver cancer in people with hepatitis C, including dietary supplements such as carotenoids and vitamin K, but the evidence is too limited for conclusions to be reached.
References
- Azocar J, Diaz A. Efficacy and safety of chlorella supplementation in adults with chronic hepatitis C virus infection. World Journal of Gastroenterology. 2013;19(7):1085-1090.
- de Avelar CR, Pereira EM, de Farias Costa PR, et al. Effect of silymarin on biochemical indicators in patients with liver disease: systematic review with meta-analysis. World Journal of Gastroenterology. 2017;23(27):5004-5017.
- Diglio DC, Fernandes SA, Stein J, et al. Role of zinc supplementation in the management of chronic liver diseases: a systematic review and meta-analysis. Annals of Hepatology. 2020;19(2):190-196.
- Farias MS, Budni P, Ribeiro CM, et al. Antioxidant supplementation attenuates oxidative stress in chronic hepatitis C patients. Gastroenterologia y Hepatologia. 2012;35(6):386-394.
- Fried MW, Navarro VJ, Afdhal N, et al. Effect of silymarin (milk thistle) on liver disease in patients with chronic hepatitis C unsuccessfully treated with interferon therapy: a randomized controlled trial. JAMA. 2012;308(3):274-282.
- Kawaguchi T, Nagao Y, Abe K, et al. Effects of branched-chain amino acids and zinc-enriched nutrients on prognosticators in HCV-infected patients: a multicenter randomized controlled trial. Molecular Medicine Reports. 2015;11(3):2159-2166.
- Kumar S, Ansari S, Narayanan S, et al. Antiviral activity of zinc against hepatitis viruses: current status and future prospects. Frontiers in Microbiology. 2023;14:1218654.
- Kwak DS, Jun DW, Seo JG, et al. Short-term probiotic therapy alleviates small intestinal bacterial overgrowth, but does not improve intestinal permeability in chronic liver disease. European Journal of Gastroenterology & Hepatology. 2014;26(12):1353-1359.
- Manns MP, Wedemeyer H, Singer A, et al. Glycyrrhizin in patients who failed previous interferon alpha-based therapies: biochemical and histological effects after 52 weeks. Journal of Viral Hepatitis. 2012;19(8):537-546.
- Rambaldi A, Jacobs BP, Gluud C. Milk thistle for alcoholic and/or hepatitis B or C virus liver diseases. Cochrane Database of Systematic Reviews. 2007;4:CD003620.
- Seeff LB, Curto TM, Szabo G, et al. Herbal product use by persons enrolled in the hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial. Hepatology. 2008;47(2):605-612.
- Yang Z, Zhuang L, Lu Y, et al. Effects and tolerance of silymarin (milk thistle) in chronic hepatitis C virus infection in patients: a meta-analysis of randomized controlled trials. BioMed Research International. 2014;2014:941085.
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