Lipidomic markers for Hepatitis C and related conditions, treat hepatic fibrosis and hepatocellular carcinoma. An agent administered to such subject may be an cellular total fatty-acid content under iminosugar, which may be effective against hepatitis C. Such iminosugar may be, for example, one of N-substituted deoxynojrimycins and pharmaceutically acceptable salts thereof, N-substituted deoxygalactonojirimycins and pharmaceutically acceptable salts thereof and N-substituted Me-deoxygalactonojirimycins and pharmaceutically acceptable salts thereof. A method of assessing a Hepatitis C infection or a condition caused by or associated with said infection. This method comprises: obtaining a biological sample from a subject in need thereof determining a level of at least one Hepatitis C lipidomic biomarker in said biological sample and comparing said level of with a control level of said Hepatitis C lipidomic biomarker to assess the Hepatitis C infection or the condition caused by or associated with said infection in the subject.
