Hepatitis C and Dietary Supplements: What the Science Says
Clinical Guidelines, Scientific Literature, Info for Patients:
Hepatitis C and 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.
Current research suggests that milk thistle is no better than placebo as a treatment for hepatitis C.
What Does the Research Show?
- 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 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.
- A 2009 Cochrane systematic review assessed the beneficial and harmful effects of milk thistle in patients with alcoholic liver disease and/or hepatitis B or C liver diseases and found that there is not enough high-quality evidence to support the use of this intervention.
- 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.
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.
- 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.
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 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.
- A 2012 study evaluating the effects of vitamins E, C, and zinc on oxidative stress in patients with hepatitis C found that the antioxidant supplementation had a protective effect on participants, attenuating oxidative stress related to the disease.
- Zinc is generally considered to be safe when used appropriately, but it can be toxic if taken in excessive amounts.
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.
- 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.
- Azocar J, Diaz A. Efficacy and safety of Chlorella supplementation in adults with chronic hepatitis C virus infection. World J Gastroenterol. 2013;19(7):1085–1090.
- Farias MS, Budni P, Ribeiro CM, et al. Antioxidant supplementation attenuates oxidative stress in chronic hepatitis C patients. Gastrienterol Hepatol. 2012;35(6):386–394.
- Fried MW, Navarro VJ, Afdal 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. Mol Med Rep. 2015;11(3):2159–2166.
- 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. Eur J Gastroenterol Hepatol. 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. J Viral Hepat. 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 Res Int. 2014; 2014:941085.
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